The "ugly, boring, still here" observation matches mine exactly, and I think the reason is worth naming.
An app with no revenue has no reason to redesign. Nobody has to justify a quarter. So the thing you learned in 2019 still works in 2026, the settings are where you left them, and it does not one day decide to become a social network.
Whereas the polished one with a subscription is under permanent pressure to grow, which is where the assistant sidebar and the discovery feed and the account requirement come from. The polish and the enshittification are the same funding source pointing at different quarters.
The honest cost is real though. I have handed one of these to a family member and watched them bounce straight off it, because "a wall of checkboxes" is not a joke: it is a genuine barrier, and telling someone their file manager is principled does not help them find a file.