I also think the standard of “what is acceptable?” was much lower back then.

I'm not sure that's true. Here's the UI hall of shame, highlighting the worst of the 90s: http://hallofshame.gp.co.at/shame.htm

Most of the stuff there would be just... normal now. It's quite unusual for SPAs to have a decent consistent UX. And the slowness would never have been tolerated back in the day.

the author of that page seems to believe that mouse hover feedback is bad, even when it's a simple highlight?!

I think that's mostly it. Design has a much larger role, and form-oriented development with common controls doesn't cut it. You couldn't imagine an app like Facebook in a forms-style UI, it's almost ludicrous to imagine.

Looked at retrospectively, forms were just one step above green screen applications on a terminal, transplanting one set of structural idioms to another, like for like.

If forms are essentially terminal apps, is FB much different from a teletype news service, with hyper-filtered content and an infinite set of data sources?

I see massive sea change in connectivity and immersiveness of today, but not really in what we're trying to achieve.

2001 was Mad OS X Cocoa. 2020 is JavaScript. The standard for UI was higher then, but was lost to the almighty god of cloud-based web apps.

or MS Access, or Hypercard - we've had productivity boosters, just never anything remotely close to eliminating the inherently hard act of "building software".

Yes, but that GUI was only doing local work, we have much higher requirements today.

The GUI was doing local work, but the database could be remote. Delphi's name is even a pun on Oracle.

I'm not saying they were halcyon days. I'm saying that the effort to do things is not necessarily less these days, in part because we have different expectations (not necessarily requirements) today.

It's even easier to do so with no-code, low-code tools.

In 2000 using VB, you can build a GUI, make a working Windows application using a minimum amount of code. Also the documentation (msdn) and the community was really nice.

20 years on MS Access has been one of the quickest lowest code way to build a functional application. What a mess everything is these days in comparison.

If you wanted to build a data entry / collection app with basic validation, querying, filtering etc. you could easily do that with no code in 2000-era Delphi.

With support of today's API's/datasets , you could build more complex apps with similar levels of effort.