texansky EA_Solaire has replied in the master thread about the website outage:
Sims 3 website is down? | EA Forums - 12899232
As far as I've read, it's considered a real problem that really needs fixing, not an unofficial sunset of the site. As for this website, it's had its issues since it went live, with many being resolved and some new problems appearing as the site has been built out. You can post feedback here (I think you know that already, but others reading may not):
Questions & Feedback on EA Forums' functionality | EA Forums
The site signs people out if it's been more than eight hours since they signed in. I think this is by design but don't know that I've seen confirmation. If you're being booted more frequently, a report might be useful to the forum admins.
At any rate, the issues with this site have nothing to do with how EA feels about Sims 3. The site issues affect all games' forums more or less equally.