Apparently there is a new .onion format that is very improved and works faster. But still, all the encryption and so on will always make things slower than clearnet. So this default slowness will make things as bad when ddos'd or even worse (even if ddossed have a harder time ddossing, it will still be effective)
Tor runs quite quickly on my computer.
My internet history is very long on firefox so when I put it to connect through tor it doesn't slow down very much.
The solution is most likely a blockchain based forum. Perhaps with sidechains somehow we can use BTC's blockchain to host a forum? who knows. I just hope it doesn't require javascript. Cloudfare forces javascript and then add the google catpcha. Not good.
I don't think theymos likes to hand out copies of the forum (as it opens up the potential for the site to gain phishing attempts).
The login stuff would still need to be done by the loginserver otherwise there would be a lot of issues (unless we get masternodes that moderators and legendaries can have which can allow users to autehnticate their way onto the website)...
All of the core devs also seem to have ditched bitcointalk so I'm not sure how kindly they'd take to a suggestion of hosting it.