That’s the point – your claim about deb-based distros is just anecdotal.
The example here is Nvidia updates borking the system. I’ve have that happen to me numerous times on Arch-based systems.
I’ve run deb-based distros on some boxes over years of updates with no issues. On the other hand I’ve had updates cause breakages on Arch-based systems pretty much every time I’ve run them.
Which is to say anecdotes are useless, updates can break systems, and being able to immediately roll back to a working system and deal with updating later is a simple, nice thing to have with no downsides.