OK, my take....

Having spoken to ATC guys up,and down the east coast of the US (I supported equipment for airports and ATC) as well as a number of "heavy iron drivers".... the pilots and their company want them high and fast as long as possible, why? Fuel economy.

ATC wants them below 10k' so they are below the 250kt limit. This is to handle busy airspace and help with workload.

I feel the current US bills on ATC are airline centric.

Pilots want to be higher.
Commercial airlines want to be higher due to costs.
Most GA (gliders included) want heavy iron higher to stay away.

If ATC followed the US "wedding cake", most issues go away......most.

Yes, you still have private jets (small number) and corporate or "undetermined" in the mix, but rather small numbers.

Hoping these pilots make a comment, but I believe they will agree. "Stay high for fuel, slam dunk to a landing". Good on costs, less "crap" to avoid.
At minimum, stay above Cu cloudbase, unless wave is happening, a bit less to avoid, especially on a weekend/long weekend.

My unedumacated $0.02