12 years ago I devoted a year to test my theories (wrote my own software) to find out what I wanted to know. Paid a motza for data in those days too.
Takes dedication and time.

Never looked back.
Beats 9 to 5 or whatever hours you work.

Instant millionaire? Don't even think about it.
Making a good living? Oh yes.

Racing changed in the meantime? Probably, but my system/rating still works the same.

Every horse still has to run the same distance carrying the allocated weight with a little man/women doing his/her thing on it's back according to instruction. (wherever they come from?)

Good luck