There's actually a big scene of vegan cheese alternative making, it's just pretty localised right now. For example there are many companies in London making excellent vegan alternatives (e.g. I AM NUT OKAY, Honestly Tasty, Kinda Co, Mouse's Favourite), many of which offer something with pizza-melty mozzarella-like effect. Local pizza delivery places offer the vegan options too. There's even some with blue mould for that real funky cheesy flavour! It's expensive right now but the product is there.