They did give us XMLHttpRequest… but yes, it's mostly been downhill.
I think I did the right thing blocking LinkedIn years ago. Too many emails claiming: "Ohh, {mips,mozilla}@gentoo.org… so-and-so thinks they know you, can you confirm?!"
I while back I blocked ALL cookies related to Twitter (and now X), which prevented the website from loading at all. Out of curiosity, I lifted the block to see what it was setting--25 MB of cookies. Wild. And yes, I thought--definitely for the best.
@briankrebs this happened a few years ago to me, as I used to use a 2010 iMac, and Apple stopped updating Safari for it (other than security updates). LinkedIn decided that instead of just letting me see “broken" CSS and JS, it was better to just show me a page scolding me for using vintage software.
Which in the end meant I avoid ever visiting it on my newer devices as well.
@briankrebs I just tried Chrome (I normally don't use it) and it opened the site just fine. Didn't try to log in, though.
New visitors are presented with a cookie banner. If something in your browser hides the banner, you can't click on the Accept/Reject buttons and since the banner is modal, you can't click anywhere else on the site, either. Maybe this is what you're observing. I've had this happen with Opera on another site. Try incognito mode?