Wouldn't advise turning off ipv6. We are probably getting near the point where some public services will disable or offer v4 as only best effort, and when this happens, your connectivity will be broken for certain things if you disable v6. Heck, it's to the point now where all my home hosted services are v6 only.
The better solution is to just get a VPN that supports ipv6 like airvpn or mullvad. I think pia disables ipv6 while the tunnel is up, which is better than disabling ipv6 altogether.
To validate the tunnel is working properly you can use something like this.
There is also a Torrent Address detection section, that when you activate it, will provide a magnet link that will show your ip to ensure that it is tunneled properly.
Many ISPs are no longer handing out even 1 public ipv4 address per account, and instead opting for CGnat which further breaks and stratifies the internet.
Tmobile for example is 464xlat which is even worse than cgnat since it requires tampering with dns responses.
Given the situation many ISP are in, most serious companies offering services on the internet have supported ipv6 for a long time now in order to offer the most competitive service possible. And with cloudflare now serving up a large amount of traffic, a lot of all traffic is v6.
Don't be so quick to paint everyone with the same brush. I have had my Ccna since 2003, he.net ipv6 sage since like 2009, netadmin for literally millions of nodes. Architect for even more.
And I still disable ipv6 on most machines for personal use.
I actually had to disable ipv6 just because Halo Infinite wouldn't load the UI. A couple websites were unreachable with it on too. Seems like it will still be awhile.