Right on Kirby! In this industry we're not selling gear, music, add-ons nor experience (to a degree at least); we're selling ourselves and our personalities.
If all you do is worry about what the other guys are doing, you'll end up spending all your time chasing them instead of creating and innovating and making them chase you. As for the analogy of someone doing a better job for a smaller salary getting the job/promotion, you've only got part of the equation. Ask any recruiter or HR manager, the job output is a small part; the larger and most important part is personality...are you a good fit for this company/work group/team/position, etc. If you're not a good fit, you can have the best work at a company, but you're still not going to get that promotion. Translate it back to competing for brides and what does it mean? It means if you and your personality/style is the right fit for the bride and groom then you'll be the one getting the job.
Dude, if you're worrying about the 20-something taking gigs from you, then you've got a lot bigger issues than who is taking a gig from you.
I know people don't want to hear it, but it's the personality of the DJ that makes all the difference and that's what will set you apart from anyone else.
I can buy the exact same gear and music as you, set it up identically to you and play the exact same songs as you. I can belong to the same organizations as you, I can market myself the same as you, I can also tell brides the same things you do. I can dress the same as you, comb my hair the same as you, if you wear glasses I can get non-prescription glasses that are identical to yours. I can be your identical twin in every regard except one...personality.