Hey!
Theymos didn't condemn mixers;
The purpose of banning mixers isn't because mixers are used by criminals.
Infact, banning mixers is against theymos wish;
If there's a fair alternative to this, theymos wouldn't have announced the ban;
Theymos is doing this for the sake of the community and Bitcoin.

If your account is deleted and more hundreds of accounts belonging to your friends are banned, it will make no strong news. But if FBI or US government bans the first and largest cryptocurrency forum, it will be another win of the government against bitcoin. So, theymos is just cautious.