Well maybe the FARs should have required you to hold an ATP. Part 121 should require an ATP for every seat. I'm not quite sure how your examples are germane except to show that school training does not necessarily qualify one for the profession.
Don't get wrapped up in the ALPA name. Should our profession have some say in who and how someone can enter? I just used ALPA because it is easier to type than naming every union. And as for "artificially" shrinking the market, it's not artificial. It's basic supply and demand. Tightening the requirements for operating a Part 121 aircraft is not artificial. Personally I think it is long over due. We are seeing the results of lax training and hiring standards of the small carriers in the accident numbers.
I'm only talking 121 ops. 135 and 91 ops would have their own rules. An ATP is not needed to sit in the right seat of a Beech Jet. An ATP should be required to sit in the right seat of an airliner.
This is just an abstract idea in response to your rejection out of hand to the previous poster. The FAA is failing in it's safety mandate. Maybe a little help from the unions would be beneficial.