I don't know of any other viable alternatives, but honestly, I haven't looked because I didn't need to. I suspect this site is "mainstream" in these topics, but knowing the internet, there are certainly smaller communities.
From the UK, I've heard practically nothing but negative news. My only advice is a VPN.
Even China hasn't been able to completely block VPNs, so the UK won't be able to do so anytime soon either.