I still see people uploading to the Sims 3 Exchange despite the fact that EA clearly abandoned it, and I find things I want to download, but the site just won't let me.

I can get onto the site fine, but when I click to login (because it doesn't let you download anything if you aren't logged in), it says the website can't be reached. I've tried it on Google Chrome (my default browser), Firefox, and Edge. This can't even just be my issue, because I checked it on a Down Detector website (Down for Everyone or Just Me) and it always says that it's down. It's like it's a dead link that EA didn't update or something.

I did notice that at first, when I clicked the Exchange link from my game launcher, it opened in Internet Explorer with my account already signed in. When that happened, I was able to download content again. However, through some random mishap, the website logged me out on Internet Explorer, and now I'm unable to sign in again for some reason. On Internet Explorer, it says something about it being related to TLS settings, as opposed to Firefox and Google Chrome where they just say they can't connect.

I've seen other people on here saying that the Exchange still works for them, and I can see that the new uploads people post to the Exchange are being downloaded by people, so I don't understand why I'm seemingly the only person who has been permanently shut out of the website.

Is there something I'm missing here?

Try the workaround I posted here:
https://modthesims.info/showthread.php?p=5882801
It works for me but you need to see the page of the download you want (or have the asset number). I am able to browse the exchange without logging in though, so hopefully you can.

That's good to know. I actually discovered yesterday that when I use the Pale Moon browser it lets me log in, so I'm probably just going to use that now lol