Am I stupid for only doing 3 sets of a single exercise and then being done for a few hours?

I hate 40 minute long workouts, so I tend to just avoid them and it makes me really inconsistent where I might do a workout one week, two the next week and then zero the next week.

I’ve got three routines that I’ve built in involving push, pull, and legs with five or six exercise exercises in each

I really don’t mind doing a quick five minute exercise where I’ll just do three sets of pull-ups for example, or I’ll do three sets of dumbbell bench presses and then come back a few hours later to do a different exercise from my routine

Are the results from this going to be dramatically different than if I was just consistent doing these 40 minute routines that cover all the muscles in the push/pull/legs group?

I know that doing anything is better than nothing but I’m just looking for how dramatically different the single exercise versus a full routine approach would be