I wasn't on Smashboards until recently but I've always played smash. Melee combos at the highest level may have seemed longer, but that's because their were about 7 top characters that got used in incredible excess because they were just better than the rest of the cast. I'm sorry if I sounded condescending, but I'm actually of the view that with P:M's more beginner friendly inputs and tech, it opens the combo game up to many more players. I don't quite agree that tech chase combos aren't true combos since if executed right have the same effect.
One other thing that not a lot of people think about is that the Project M metagame is very larval in its current state. You have very few superstar players compared to melee, and the metagame hasn't had a very long time to develop. Better players on these forums consistently say when all the players in P:M start to rise the punishment game will rise with them and more resemble what you're talking about. If you watch Strong Bad's DK, he confirms kills off of most hits. Straw Hat tears people apart with Falcon once he gets his approach. Armada zero to deaths a lot of players with his Pit.
I think what you're seeing is the development of the meta in its relatively early phases, which is why the game seems less combo heavy than Melee, except in a few specific instances. But that is a byproduct of itself rather than the game being less combo oriented. Especially with that "take a potshot and back off" thing. I know exactly what you're talking about, and I see it happen too often, even at a high level, which is just a show of how a lot of players are getting by an understanding of meta and playing their opponent rather than knowing the right tools for the right situation.
Also, out of curiosity, how do you have 20 posts after being here for 8 years?