I don’t know the pros and cons of each but most coaches I have seen have taught to step with the non racket foot.
I did at one point have a beginner level coach that taught racket foot stepping. But he would teach standing very far back. So what he showed isn’t comparable to a pro doing a step with their racket foot
When I would step with my racket foot years back, coaches would tell me to step with the non racket foot, as they do and that’s how they learnt it.
I don’t know if the some pro players stepping with racket is a newer thing.
Sometimes I heard racket foot stepping as something for some of the women players. Being shorter. They need that extra distance. But no doubt tall men may do it too. Like I saw a video of Greg of bsdmintoninsight showing it. And saying he gets closer to the shuttle.
I found I got better return of serves when I stepped with non racket foot.. that is partly because it’s a smaller movement and easier to time. And partly because I haven’t been really coached to do it well with the racket foot
No doubt if I ever saw a coach that taught the racket foot step I would try it with them and could get good at that one and then compare with the non racket foot step, but I haven’t done that. I’ve either not been coached on the racket step one, or not been coached to a comparable level as the non racket foot me.
Maybe somebody that can do both to a very good level could address your question. It’s complex.
Many might have been adamant on stepping with non racket foot being ideal. But if/when some pro men step with racket foot then it calls that presumption into question.
So, I’m interested in a good answer to your question but ultimately what your coach does and teaches is what you can get good at.
What I was once taught is that if you stand close to the front and have your racket out then you don’t need to step with the racket foot, you only need a little movement with the non racket foot. But since some pros so it one could say that with great speed it could be possible to totally nail it incredibly with a movement of the racket foot and get super close. But that’s very advanced.
So, there could be a justification for the racket foot step, at a very beginner level or if quite short.. and being a bit far back.. Or, at a super advanced level
One other thing though, if they low serve wide , you have to use the racket foot. So that’s an easy question. But what I’m talking about, and what you would be talking about if your question is good, is if they serve low and not wide So, when you have the choice.
Maybe it’s a complex subject.
I don’t think it is a subject that is well explored.. some years back I know coaches would say use non racket foot not racket foot. (with exception of some women, or a beginner player that is super far back).
Maybe now they say differently and are more open minded on it? I don’t know. It’s a good question.