It was really good, as someone who flew pre 9/11. I remember reaching Logan airport 20 minutes before my scheduled flight in 2001 thanks to Boston's traffic. I walked to the gate unimpeded (nothing to check in). Zero stress.
Part of it is also that flights used to be much less overbooked and the overall experience was better and this isn't just nostalgia.
However I don't think it's completely fair to blame the TSA for the worsened experience. The threat model has changed since then. Add to that shrinking seats, worse customer service, more crowded airports, and the experience is much worse.
A few years back, we decided to minimize air travel and take a lot more local vacations. Yes, we miss flying but at some point the hassle exceeded the desire to visit exotic locales.