Like a flock of migrating birds, smartphone makers tend to move from one new trend to the next in groups. One moment, you have an aluminum iPhone 6S with a headphone jack and no notch, and the next, you’re watching the phone market become overrun with iPhone X clones that omit the jack, embrace the notch, and ditch the metal. The last major name still standing by aluminum as its construction material of choice was Google, and that laggard behavior was corrected yesterday with the launch of the all-glass Pixel 3 and 3 XL. Now, the aluminum flagship phone is well and truly dead.

The very first aluminum smartphones to make their way onto the market came almost a decade ago. They were the HTC Legend and Nokia N8 in 2010. HTC was especially bold in crafting a literal unibody shell for its phone, emulating Apple’s celebrated MacBook Pro design of that time. It left only a couple of small rubber sections on the back of the device to let wireless radios work and to give users access to the battery, SIM card tray, and memory card slot. Yes, we used to have all these things. The Legend also had some features we no longer miss, such as an optical trackpad, a set of awkward physical buttons, and a massive “chin” at the bottom. As to Nokia, its anodized-aluminum N8 and E7 phones from that era still stand as iconic designs, the latter of which also had a physical keyboard that popped out with a violent mechanical snap.

I guess I’m feeling sentimental in part because the maturation of the smartphone market is inevitably accompanied by its loss of diversity. As the iPhone has risen in cultural prominence far beyond the tech industry, it’s also taken on the mantle of defining the popular idea of what a smartphone should look and feel like. Samsung and LG’s perseverance with the headphone jack in their flagship phones is a minor revolutionary act in the face of an industry that appears willing to follow Apple to the deepest reaches of dongle hell.

Apple moved away from its aluminum iPhone design with the glass-backed iPhone X and iPhone 8 in 2017. The reason for that change, I have argued, was as much about differentiation from the competition as it was about opening up more technical possibilities with a different production material. As far back as the iPhone 6S’s release, Apple’s rivals had perfected their own aluminum unibody designs that were nearly identical in their look, feel, and quality of manufacture. Apple had to change if it was going to maintain the air of exclusivity and exception about the iPhone. It also had to ditch the metal if it was ever going to do wireless charging, which Samsung had already been offering since the Galaxy S6.

Everyone is riding the all-glass bandwagon now

Before long, everyone was aboard the glass-back bandwagon. Some got there before Apple, some after, but as of today, every major name in the mobile industry offers a flagship phone with a glass back, whether it’s the Samsung S9 or Note 9, the HTC U12 Plus, the Motorola Z3, the Sony Xperia XZ3, the OnePlus 6, the Xiaomi Mi Mix 2, the LG V40, or the Huawei P20 Pro. Or the Google Pixel 3.

This is what the soft-touch coating on my demo Pixel 3 looked like. Scratched to hell. This is day one. pic.twitter.com/Rdh3NppGE3 — Ron Amadeo (@RonAmadeo) October 9, 2018

My issue with having glass on both the front and the back of a phone is prosaic but fundamental. Glass is fragile, so doubling up on its content in a phone obviously increases that device’s fragility. My trusty Pixel 2 XL, the aluminum forebear to the Pixel 3, has countless scrapes, bumps, and gashes from the times I’ve clumsily dropped it. I’m confident that the falls that device has taken would have resulted in numerous shattered backs on a device with glass on both sides. Hell, I managed to break the handsome but delicate frosted glass back on the Xperia Z5 without ever dropping or mishandling it. Glass is always a design compromise for anything intended to be handled by humans, imperfect and easily distractible as we are.

The Pixel 3 devices that Google showed off for the first time yesterday were already exhibiting signs of being rather scratch-prone, especially the black ones. Ars Technica’s Ron Amadeo noticed that his review device had picked up scuffs, YouTuber Marques Brownlee reported “several microscratches within minutes of unboxing,” and I witnessed multiple demo Pixel 3s at Google’s London event with abrasions in their matte black glass back. I can’t say the same thing about the white and so-called Not Pink color variants of the Pixel 3, so it’s probably just the finish atop the black Pixel 3’s glass that’s wearing off, but it does spoil your beautiful — and expensive — new phone very quickly.

The question that no one in the mobile industry seems to be asking is, what about polycarbonate? I refuse to forget how sumptuous the Nokia N9 felt when I first handled it. It was a short-lived MeeGo smartphone crafted from a thick, pillow-shaped polycarbonate slab that gave it both gorgeous color and fantastic ergonomics. Nokia kept that design going with the Windows Phone Lumia 800 and other devices, and everyone who ever laid hands on those phones has walked away impressed. The failure of Windows Phone unfairly demised that design lineage, and no other company has seemed interested in picking it up since then.

Well, I happen to think consumers are interested. Offer any of your friends a choice between a glossy, fragile, fingerprint magnet of a glass back or a matte, colorful, and durable polycarbonate shell, and I imagine most of them would go for the latter option. Polycarbonate is as transparent to radio waves as glass. You can always build bad plastic phones, of course, as Samsung has previously demonstrated. But all this precise glass engineering and manufacturing can’t cost much less than using a well-thought-out polycarbonate design, such as the ones Nokia used to make.

I’m perfectly at ease with bidding adieu to the metal smartphone. It was always a contradiction, anyway: a device intended to be constantly connected to everything around it probably shouldn’t be enclosed in a shell that makes wireless connections difficult. But the way that the entire mobile industry has decided that glass is the only alternative disappoints me. Glass is far from the perfect answer, phone makers shouldn’t accept it as such, and I hope 2019 brings back some of the design diversity that made smartphones so exciting in the first place.