Yes they can, but claiming a theoretical future event as fact (or inevitable) I would consider particularly fallacious as it's impossible to prove.

And I think history also shows these claims rarely end up happening the way these alarmists think it will.

Usually when a slope appears, regulation steps in, technology evolves, or the culture shifts, rather than society devolving into some inescapable dystopian hellscape.

Google has been following the trend of locking down Android for a decade. The slippery slope is a fact here.