Entrepreneur Vinny Lingham’s transaction fee poll has revealed the community believes $1 fees are not “sustainable” long-term.

1,781 people responded to the poll on Twitter, which asked: “Transaction fees for Bitcoin are now greater than $1 on average, & rising. Assuming no 2017 Segwit/Block size upgrade, is this sustainable?”

Of those who cast votes, 31 percent believed such rates were unsustainable, with an equal proportion stating indifference.

Just 23 percent thought the fee amount was sustainable, and another 15 percent claimed not to know.

Transaction fees for Bitcoin are now greater than $1 on average, & rising. Assuming no 2017 Segwit/Block size upgrade, is this sustainable? — Vinny Lingham (@VinnyLingham) May 10, 2017

Lingham has frequently voiced concerns about rapid Bitcoin price growth and the potential “bubble” effect that could result. In the event volatility returned to the market, businesses, adoption and Bitcoin’s overall image would suffer, he intimated in several blog posts earlier this year.

More recently, attention has again focused on the cost and relative time needed to process Bitcoin transactions, as first SysCoin and Vertcoin and now Litecoin activate SegWit. Soon, Lightning Network technology will also deploy for Litecoin, allowing for near-instant transactions.

Responding to the poll results, fellow entrepreneur Tuur Demeester noted that “very little complaints” could be found on darknet markets regarding the fees. “Suspect we can go up to $5 for that use case,” he added, also highlighting Bitcoin was still the darknet’s currency of choice despite the cost savings of altcoins.

Total transaction fees paid to miners are hovering near all-time highs on Thursday.