Eventually the FI market will get flooded too, it' s only a matter of time.
I would prefer to see people spend 5K on a FI course than 30K on a TR.
As an FI, aside from the money-earning aspect, you become a better, safer pilot and get to know yourself alot better (as a pilot).
A TR doesn' t make you a safer pilot, you just stuff your brain with (potentially useless) information, learn to fly a 5 by 5 box on a computer screen and stuff your TR school' s pockets with money.
FI as a career:
Career FI' s can be better or worse. I' ve seen some very good ones that would fly circles over the best non-career FI but I' ve seen some bad/arrogant ones who have gotten students injured (not only morally) due to their bad decisions and/or lack of humility.
As a general rule of thumb, non-career FI' s tend to focus more on airline-like aircraft operations, career FI' s will tell you all about how to fly a Cessna and all the way up to a Mooney or a Seneca but will not talk about how they relate to a jet.
Point being, FI is not necessarily only a career thing IMO.