There's nothing wrong with wireguard at all if you already have the hosting service available. The core value add for Tailscale is that they provide/host the service coordinating your wireguard network.
If I'm not mistaken, there's a self-hosted alternative that let's you run the core of Tailscale's service yourself if you're interested in managing wireguard.
I meant to say hosted service there, I.e. running a wireguard server to negotiate the VPN connections.
The main reason I haven't jumped into hosting wireguard rather than using Tailscale is mainly because I reach for Tailscale to avoid exposing my home server to the public internet.
There may not be an issue at all, I'm just gun shy about opening any ports publicly. I don't do networking often and have never focused on it enough to feel confident in my setup and maintenance.
If I'm not mistaken, there's a self-hosted alternative that let's you run the core of Tailscale's service yourself if you're interested in managing wireguard.