Their store and possibly their entire main OS menu sure feel like "webshit" on the PS4 and PS5. I'd be pretty surprised if they weren't using Webtech for layouts, formatting, and scripting (with Javascript).

On the PS3, only the store was webshit, and it performed so amazingly poorly (and crashed all the time) that I never bought anything on it, and I doubt I'm alone in that. The PS3 could have handled a website well (obviously), but not the trash heap of a "web app" they used.

From what I can tell, they didn't learn a lesson from this, they've just benefitted from beefier hardware to keep their newer stores usable (and I may be imagining it, but performance on menus and in their store already seems to have declined a lot from when I purchased my PS5).

Given all that, I'm not sure how much Javascript performance they can afford to give up without making their entire system's UI experience totally suck. They could improve the quality of their system and use of web tech to improve performance, like it's a joke any of this isn't perfectly, buttery smooth on a system that powerful even if it is Javascript and HTML and CSS... but given they never seemed inclined to do that even in the pre-AI-slop days...