[n144q]

Of course you get pushbacks. Is there any *real* advantage, technical or otherwise, at an organization level, of adopting this new model of creating web pages, other than your personal preferences? You are moving away from an established system with tools that everyone is familiar with, to a system that much fewer people use, with no clear performance/maintenance/management benefit (at least not demonstrated). Maybe you don't like writing JS/TS, but plenty of other people do, and they don't need to cater to your preferences.

People need to spend time learning this tool. They need to be proficient with it. Your new stack might need to still work with existing code at some point. That means training, overhead, ramp up and potential risk in a less established area. Why would people do that?

You should be thankful you didn't get warnings from your boss for messing around instead of actually pushing features out.