Alex
Rob ⚡️ The feature is turned off by default. You can enable it anytime in Settings, refresh wallpapers, adjust your preferences, or choose to access it only by swiping left. Everything stays in your control.
Built with privacy in mind, Lock Glimpse will soon let you display your own photos on the lock screen, replacing all other content and making every unlock uniquely yours.

It says specifically:
Rob ⚡️ Lock Glimpse will soon let you display your own photos on the lock screen, replacing all other content
So currently, as this is a beta update, this is just a preview of a feature, nothing else. If they push ads and make anything against that quote above then yeah, it won’t be nice. But we can’t see the future 🤷♂️
The guy in the vid turned it all on to make some drama out of nothing, internet as usual.