I had a contract once to save a government website that had serious performance issues, it was so unusable that people preferred to go in-person and wait 4h in a queue rather than try to fill the forms online.

The frontend was in React because the company that got the contract initially used React for everything. The frontend was a 5MB SPA, but it could've been (mostly static) HTML files with some interactivity for forms like TFA. Everyone working on the project agreed React didn't make sense, but we couldn't do anything about it because someone from the government IT department would have to admit they made a mistake. There was no budget for rewrites in the contract. The few times a developer attempted to remove any "React monstrosity" they got in trouble.

Sometimes developers care, but the people in charge don't, and in government environments every change must go through them first.