In contrast, the people who learned at the hands of mentors always showed more interest in actually becoming good at the trade, and favor practicality over theory. They will usually work to fill their own gaps in knowledge, and become some of the lynchpins on any development team.
I'll take an earnest, self-taught person coming up from the QA department every day over a greenhorn fresh out of college.
Neither of those things are "minor felonies". They're misdemeanors, and don't close all those doors. Felony convictions hover around 8.6% of the population based on a cursory Google search, and most non-drug related felonies are serious business.
If you do get convicted of a felony, yes, your life as you know it is over (can't vote, can't own guns, etc etc) However, the two offenses you state are not felonies, unless you've hurt somebody while drunk driving or you possess enough drugs to indicate intent to distribute.
At the same time, it seems a bit much to say "your life as you know it is over". Lots of people don't vote or own guns anyway.
Uhm, that's not the only problems you face. If you're not aware of it: you don't get a lot of federal benefits, credit etc is screwed, noone will rent you their apt etc., unemployable for almost every job except janitor etc.... your life is over.
Note that none of the jobs you list would ever allow someone with a criminal record. A minor felony conviction (drunk driving, drug possession etc) closes all of those doors.