They're both doing the same thing. And Garmin probably impacts users negatively (financially) more
Garmin watch prices have gone through the roof Garmin doubled the price of their marine chart plotter app for me (Formally Navionics,), so I switched to a competitor.
Garmin added connect+ to their fitness platform so after spending $1000 for a watch you can pay an additional subscription to get the rest of their services
Strava put half their stuff behind a paywall a half dozen years ago causing me to stop sending them my data for free and deleting my account Now they're trying to bite the hand that actually feeds them data by going after Garmin. Pretty sure Garmin users would be 90+% of the data coming into Strava.
Garmin just has to sever syncing to Strava and it would all but shut them down.
It's greed, to keep growing yearly getting fatter and fatter at the consumers expense.
I've been using Garmin watches (runner) since like 2013 and had Navionics since sometime around the same time. I only know how to protest these companies with my wallet or data since they won't listen otherwise. Not sure if I'll buy another Garmin watch when this one is due for replacement. Depends on how much stuff is behind "connect+"