I have a few personal things hosted on IPv6-only just for giggles. A few years ago those things would almost never be reachable. Now I can reach them at most places. I at least have IPv6 on cellular connectivity all the time.
Let's say that I am considering this too, have looked a bit into it, but I am not a network engineer, and haven't done it yet, so I am not sure how good that advice is ?
I guess this depends a LOT your ISP, and especially the router they gave you, how much IPv6-only friendly are they ?
Yes, you can buy your own router, but this come with even more complications and potentially negotiations with the ISP.
( Your ISP should give you at least a /56 : https://www.ripe.net/publications/docs/ripe-690 )