Why would VPS provider need to be trustworthy at all? They just need to be reliable. Having VPN doesn't absolve you from securing hosts within it, like you would in any other network. VPN just simplifies the networking.
And if they're not reliable, VPS providers are much easier to switch than "Tailscale".
I was not claiming Tailscale has to be trustworthy.
Though, thinking about it, it's a privileged software running on every node in the virtual network, that is controllable from outside (cloud). So yeah, it needs to be way more trustworthy than some static wireguard setup you setup on a VPS.
And if they're not reliable, VPS providers are much easier to switch than "Tailscale".