Just responding to a comment that said "If deorbiting in years is sufficient, the difference in time is not relevant" where it's obviously relevant.. this doesn't seem remotely controversial.
You're arguing a different thing. The topic was satellite design for satellites under 450km.
If deorbiting in years is sufficient, the difference in 1 minute vs 4 years is NOT relevant -> to a satellite builder worried about the law.
If everything deorbits within 5 years, the only way for more things to accumulate is to launch things faster. But that's a separate discussion.
If everything launched today is deorbited within 5 years, then in 5 years, all satellites will be new satellites launched after today.
If everything launched today is deorbited within 5 months, then in 5 years, all satellites will be new satellites launched after today.
Deorbit speed under a threshold has no bearing on accumulation beyond that threshold.
If SpaceX launches a trillion Starlink satellites, and they all deorbit within a year, then yes. it's going to be a very crowded year, and we'll have to drastically rethink how much stuff we have in LEO, but at the same time SpaceX would not be in violation of the 5 year deorbit window, so the issue is about how much stuff we're sending up, and not how fast it de-orbits.
"Amount of junk below 450km, total" and "Amount of junk below 450km, that hasn't deorbited after 5 years" are very different things. You're making points about total, while the original point was about deorbit speed.
