Rinks are extremely safe. They are air conditioned, filtered. In Belgium, there have been zero recorded infections from the rinks across all of last year when they were still open - limited attendance, masks, etc.
For comparison, swimming pools are open. Their showers aren't, though. Something about it not being safe, so instead people don't soap up before getting into the pool. It's gross, idiotic and all in the name of COVID.
There's a lot of these absurdities going on, it's pretty easy to find them if you look. It happens, of course.. but it is demoralizing. I'd invite you to consider how you would feel if your local government closed everywhere in the country where you could run. Closing off not just your sport, but your psychological break from the world. Your mental pillar.
Back in winter when the lakes froze, our equivalent of the parks service decided people skating outdoors, on lakes, was a COVID risk and forbade it. Even some of our official experts called it an absurd move.
And no, exercising less has had a pretty bad effect on my body, regardless of what I eat. My core and leg muscles are not doing well after 7 months not getting their daily routines on the ice, and I simply don't burn passively as much as I used to, despite doing what I can at home.
To be honest, as someone who struggled with weight most of my entire life and only got it under control after two decades thanks to those rinks, I find it pretty off-putting the way you're implying how simple it is to control weight. Maybe for you it is, but one look at obesity rates unveils the truth for most people.