In defense of tab.digital - AFAIK they move you and your data to a separate server for their paid subscription.
I’ve had no issues with my ~2 euro a month 32 gb subscription. I’ve even been able to use NextCloud Talk with friends for video conferencing in north america with workable latency.
I’ve also had them reply to issues within a day or two through a support ticket.
I think they get so many free accounts that they ignore them, and hope that people upgrade to get support. They’re probably going about it in a bad way because by not responding to their free clients people are getting frustrated and leaving because they think it’s an example of their poor service, rather than encouraging people to pay for service.
They should make it explicit when you sign up that their free version will result in 0 customer support and they’ll treat you like dirt. In my experience their paid service has been quite good - stability and support wise.
I would suggest that at 2 euros (which is what, a small breakfast?) you could try the paid support, see if it’s to your liking (responsiveness and solution-finding wise). If not, just cancel and you’re out 2 euros. I’ve heard intermittent fasting is good for you (if you have to skip a breakfast to recoup the cost).