I watched TOS when it first aired in the 60s. I can't recall if I saw the pilot then or if it was in syndication when I saw the pilot. Spock was my first crush. My kids were in elementary school when TNG came out. Star Trek is one of the strongest bonds that exist in our family. If there's ever a lull in any family gathering, we can always talk/debate Trek. My 13 year old granddaughter is third generation Trek, and she loves it as much as the rest of us.
Enterprise became my favorite. Voyager for my daughter. TNG is the favorite of my son and granddaughter. So we have a lot to debate, not to mention all the movies.