It probably has dawned on very few people that, while the A’s are just now beginning their palace coup of the Peralta College office site as their new home (“Hey, we picked it, so you should get it for us just because it would be a cool thing for you to do”) their target date of 2023 is being virtually ignored except by people who think that isn’t enough time for them to get their stuff together.

In other words, even by conservative estimates the A’s will have a new stadium around the time that AT&T Park will turn 25, which will become (depending on how the Giants are playing at the time):

- A venerable old palace of baseball with memories to last an eon.

- A slightly aging plant with nice site lines but with a diminishing number of the modern amenities that the kids like so much.

- A ratty old dump that the city of San Francisco must replace or face losing the team to . . . ohh, what the hell, let’s say Las Vegas. That’s the new destination for billionaires on the move.

Hey, mock if you must, but stuff gets old, and old is unfashionable by definition. If you want to confuse Warrior fans into stultification, tell them that the new arena will open when Stephen Curry, Klay Thompson, Kevin Durant and Draymond Green will be easing into late-‘60s Boston Celtics-hood – a roster of 30-somethings with years of 100-game seasons and the concomitant wear and tear, winning more on muscle memory that incandescent talent.

Or maybe passed up by younger, wilier teams. You never know, but age is something you don’t see coming until it’s too late.

But we digress. The point here is the transitory nature of sports, and how hard we resist the notion of aging. I mean, who ever thought the Giants would be playing in a substandard bayside park? I mean, they don’t now, but at some point their owners, whoever they may be, will look at the park as a burden rather than as a boon.

And the A’s will either be on the cutting edge of ballpark construction, which would be weirder than I think any of us is prepared to face, or fighting with a city government about who’s going to pay for the edge.

And that last possibility is really old school.