Web mining thing was removed long time ago. If I'm not mistaken, main reason of removal is antivirus programs - they don't like CPU mining and give warnings to users about it. I think that one of antivurus programs even blocked acces to Freebitco.in. So, it's not very likely that they're going to bring web mining back.
That was the reason at the time. They flag websites as malicious if they contain browser mining but even if that hadn't happened Coinhive shut down not long after so it would have gone then.
I am sure that malicious part was definitely a big deal, and I am sure that coinhive would have closed it, but you have to accept that cpu mining at this day and age wouldn't have earned all that much to anyone to make it worthwile to make it stay neither. I mean look at your website, there are a million ways to make money, this place used to be a bit more "hey get your first free satoshis entering the crypto world" where newbies who had absolutely no crypto at all had an entry point here.
Nowadays it's a giant, it's probably either the biggest crypto related website ever, or at least high at the top of the rankings and having some cpu mining situation wouldn't really be profitable at all, people are wagering 100+ btc daily here now, and that shows you how big it got.