If it's been "ruined", it was by de-regulation, then 9/11, SARS, oil, and the economic downturn and associated bankruptcies. But it's on the rebound now.

If you're talking about entry-level pilots... both civilian and military entry-level pilots get paid about twice (in real dollars) what they did 20-30 years ago. So if you think it's bad now...

Reality: Much as RAA and FAA would deny it, new regional FO's are interns and paid accordingly. A CFI transitioning to airline ops is hopelessly out of his depth and requires adult supervision. Previously experienced turbine pilots who choose to work for regionals do so for their own reasons.

Fundamentally nobody in aviation really thinks a CFI is worth $100K. Also it's a free market, nobody is going to pay them six figures when they come flocking for $30K, drooling to get their greasy mits on a shiny jet.

Doctors most certainly have this problem when a medical resident makes $30-50K. Lawyers who graduate tops in their class at ivy-league schools get right on with blue chip firms making well over six figures... and working well over 80 hours/week. Lawyers who are not blue chip material make substantially less as public defenders, ambulance chasers, or baristas.

Ultimately doctors and pilots will start low because they're passionate about the job, and passionate about making hundreds of thousands of $ a few years down the road. Other professional skills typically top out in the low mid $100K range, so they are not going to start at $20K and slowly work their way up to $120K.

Is it a scam? Of course... typically only about 30% of commercial pilot students make it to a major airline, perhaps 20% to a legacy. That's historical, odds will be better for the next decade or so.