Some of the NetworkManager VPN plugins have weird side-effects. Like the one for OpenVPN force-disables split tunnel configurations and there's no way to turn that off, meaning that all traffic routes through the VPN even if you'd rather only send stuff for certain destination addresses through.

Based on the experience that I (and other coworkers, including on other distros) had, whatever configurations our VPN needed did not seem to work out of the box on network manager.

A lot of this is just weird Linux on the desktop weirdness.

On Windows and Mac, VPN config is usually just installing a client, signing in, and then it all basically works. Sometimes you don't even need the client and can set it up in settings.

Those are pretty much all first-party clients though, right? I'm not sure that "some companies don't provide a Linux client for their software" is something I'd characterize as "Linux desktop weirdness". My point here is that Tailscale seems to have actually put time and effort into making a Linux client that's a breeze to use, whereas most of the other VPNs I've used for work have not.