If you look at it from an economics perspective, (cost/benefit analysis). The amount of time and cost associated with this aviation career VS earning potential is NOT worth it IMHO. You would be better off in the health care profession. I know many PA's, Physicians, Dentists, Orthodontists, and Opthamologists that are doing much better for themselves than most major airline pilots. For the commensurate amount of investment put in to it. Suggest you do your own cost/benefit analysis, using "worst case" scenario (CFI pay for 2 years; Regional FO pay for at least 5 years; Regional CA pay for a few years, and then Major airline FO pay for 20 years and see what you think. If it takes you 10+ years earning appx $25K/ year to get to the right seat of a legacy carrier, Will that sacrifice be worth it to you?

I started training the week before 9/11, talk about bad timing, but I stuck it out knowing that while I was in school and instructing the industry would turn around and it did. There will always be ups and downs in the industry.

The important thing is to do what you enjoy, and it won't seem like work at all.
Does it cost a lot to get started? Absolutely and yes you will not make a lot as an instructor but you certainly won't make as little as $25k a year for the first 10yrs.
I'm in my 8th year since getting all my ratings and I was making about 20k as an instructor for the first year and my first real flying job 135 was 40k.
Most of the guys I went to school with went to the regionals and are making 40- 60k.

Not trying to step on toes, just want to show another example.

I would say it has definitely been worth it and it's only getting better.

All the hard work and less desirable jobs have paid off for me. I have been very fortunate in my career. Definitely worth it!

That being said, there are plenty of people that, through no fault of their own, have had terrible careers.

I was hired at my major (Purple) at 26. It has DEFINITELY been worth it$$$$$$