Collision risk is significantly reduced by having maneuverable spacecraft with good conjunction prediction systems in place. But fundamentally, nothing is perfect and accidents can and do happen - you set a maneuver threshold based on an expected collision probability, but it's an engineering tradeoff: "spend the fuel to maneuver out of the way of everything, no matter how remote, or accept a small collision risk?"
And of course, when you are launching thousands of satellites, you will have a few failures that will become unmaneuverable hazards. Just the way it goes, you can't realistically engineer your way to perfect reliability.
So sorry, I have to reject your claims that it's "utter bullshit." Space debris risk is a well studied field, so much so that satellite insurance companies are starting to fold those calculations into insurance premiums. So yeah, it's real, and it deserves more than a pithy dismissal.
Not saying it couldn’t be bad if there were such a collision as obvi a really bad collision could in the short term damage Starlink and anyone else who decides to use that orbit, but this isn’t existential risk territory anymore.
All in all you people take the precautionary principle so far as to cripple your own progress in fundamental stuff like spaceflight but at the same time see no reason to apply it in social stuff like that survelliance camera affair or the net-id. And also fervently believe in modern version of snake oil that is "AI".
This is hypocrisy at the base level and a sign that we have a civilization crisis akin to one that of ~7th century AD.