> it becomes an issue when my product owner tells me that I need to do some funny dynamic thing

Okay, but on the other hand maybe you should do the right thing and say no.

I agree that one should push back, but I suspect we have different notions of when to do that (which is fine, my approach here is not fixed in stone). Making a page needlessly dynamic would be a concern for me if it violates business rules or for whatever reason harms the overall system. But if it doesn't do that, and it genuinely does make the business and users happy, then I'm happy to do it and then get a bit of leverage to take some time to tackle tech debt that needs addressing on the backend.

> it genuinely does make the...users happy

But you have no idea if it does that, you just have the word of the PO who's not actually building anything, they're at best just copying what others are doing (ie being derivative) or at worst just doing guesswork.

How about offering an alternative: a UI/UX that takes the web as it is, a primarily document-based format with navigation and data entry? A lot of cool stuff can be built on top of that.