Because it’s a volunteer visa in Thailand. That can’t be transferred into a working visa in Europe (or any visa in Europe). They are completely different continents with different restrictions.
Well you can ‘go’ but obviously the visa itself won’t be valid in another country. And then you have the whole issue of getting back in, doing quarantine etc.
they are unemployed but that's what many of them had to do in low season anyway. I know you all want to come back and want to think the Thai government is going to start granting 'normal' tourist visas soon - it's not. Whether you like it or not, it's committed to a high level of testing and quarantine (and I'm sure there's a lot of money going to those hotels that benefit the government). It gets a lot of kudos from UN/ASEAN for the way it has handled the pandemic (and don't get me wrong, the measures they've put in place are impressive), and it likes that. Sure message me when/if you manage to get in and tell me I'm wrong, I'd be really happy if that was the case.