Ubuntu Pro is a part of their paid-for service and one of the reasons I no longer use Ubuntu. I’m pretty sure there is a free-tier to their “Pro” service, my problem with it is that they sneak it in (apparently) to all installations which has causes many queries such as this.
So, does it matter? Well, it depends on what they do commercially … because what they’re offering is a commercial service (albeit free) there’s nothing to stop them from changing the parameters of what’s free in the future, which might mean you’re in a state where you either need to reinstall or pay. i.e. despite it being Linux, my view is that it’s no longer free in the way that it used to be or indeed in a way that people necessarily expect.
I’m very happy with my move to Debian. I don’t think I have any remaining Ubuntu installations either here or in my cloud setup. This only really came to light for me when I was looking to pre-install Ubuntu on workstations.