I understand the mechanics of LEO, and the de-orbit mechanics put in place. But the world-wide impact, unknown side-effects on the upper layers of atmosphere on the re-entry of literally thousands of satellites within fairly short period of time?

Their presence has already radically transformed the orbital environment.

There are so many that in 2025 alone they performed around 300,000 collision avoidance maneuvers.

In short: on the one hand, they're convenient for us because of their fantastic internet connection, but on the other, they're generating truly unprecedented artificial traffic in space.

All this worries me a little.