I bought a Garmin after having a Fitbit for many years. I must say i really prefer the Garmin, even though they are more expensive than the Fitbit. Though, if you want all functions on the Fitbit you need premium and if you include two years of that they are about the same price.
I’m not quite certain this will work because I’ve not used pop os in a while. Back then they used gnome so the toggle your talking about should be available via gsettings (cli). If you find the key you should be able to run a script every boot/login to disable it.
Not the easiest solution but maybe a solution.