One of the things that pissed me off fierce was when my natural gas utility company redid their website, and got redirected to a landing page with an autoplaying video. Excuse me I’m already a customer, I want to spend twenty seconds paying my bill, not two minutes dealing with unnecessary crap someone thinks looks better or more trendy.
https://xkcd.com/927/
The problem is that even if it’s objectively better, you can’t magically convert everything instantaneously, and it’s a lot more work maintaining rust and C versions of the same code until everything is re-implemented in rust.