If you are capable of setting up your own personal VPN, you don't need Tailscale. You still may want to use it though, depending on how much of a novelty Network Fun is for you in your spare time.
For me, the main advantage to Tailscale et al is that it is on a per device basis. So I can access my SMB shares or Frigate setup remotely while still keeping the rest of my internal network isolated( to the degree I trust the software and network setup). You CAN accomplish that with some fancy firewall rules and vlanning but... yeah.