All the pro racers who made it past 40 started much earlier. And were mutants.

I did my first pro race at 49. I had offers to ride with local P1/2 teams in my late 40's. Free bike, kit, and some travel money. Help the kids out.

Can you get to that level at 36? Absolutely. I started at 44 and am no genetic freak.

As CDR noted though, "paying the bills" as a full time cyclist depends on your bills. At 36, you might be able to squeak by with 3 roommates eating a lot of ramen. Same at 22. Difference is most teams are going to go with the 22 year old looking at a possible upside. Aside from physical development it takes a lot of years just to learn the sport. Most teams figure 1 out of 20 make it to a decent level. Why invest in a guy who will be over the hill when they peak?

There may be one mutant out there who can take the sport up at 36 and crush the world. One in a billion though.