It will in a while. We were in the same situation - STTN, going to sleep independently but so difficult to get down for naps. But days didn't seem to affect night, so however horrible the day was, I knew I would get a break at 7.
But as she has gotten older, day sleep is definitely affecting night sleep. Too little and we get OT wakings between BT and DF and WU is nearly an hour earlier. Same with too much -- EWs. She also picks up habits much more quickly.
4 months is hard. Naps at 4 months broke me. That sleep regression, wonder week was just very difficult for both of us.
Naps only improved for us at around 6 months. Before that, the first nap of the day was always the easiest and she slept well. After that it was a hit and a miss. At 4 months, we switched to 2 naps and a catnap and that made a difference. We accepted that the second nap was not going to improve and just stopped fighting it. So she did 1.5 first nap -- 40 min second -- 30/45 minute catnap. I would APOP the catnap in the sling or in my arms if needed - she never sleeps in the stroller.
Finally, at 5.5 months, when we moved to 2 naps, DH and I committed to staying in the room with her for the nap. So we would put her down and then go back in at 35 and lay a hand on her before she stirred. We found that she just slept through. Then we held back a bit and put a hand only if she cried out. And then we stopped going in altogether and she started sleeping through 70% of the time. I also decided that as long as she had done the first half of the nap in the crib, I would try to resettle in the crib but if it wasn't working, I would hold for the rest of the nap. Believe me, it was a weight off my shoulders. Shush/patting, PU/PD was so incredibly stressful and after all that when she still wouldn't sleep, it was so disheartening and frustrating. This way, she gets her rest and I am reinforcing our bond, and I can relax and close my eyes for a bit even. Sometimes I sit on the floor of her room and then gently lay her on a rug there.
It does get better. Or rather, when you only have to PD for 2 naps, it is less of a tension. On the other hand, not many chances to get a well rested baby when A times are long and there is only so much time in the day.
Anyway, what I mean is, if you feel that APOPing the naps is helping you, go for it. But remember, start as you mean to go. Otherwise in a few months, you will have to do a lot of extra work to break her out of the motion habit. If you feel that you can consistently continue with doing that nap in the pram, it should be ok. You can treat different naps differently.
Has anyone had a look at your routine? It is amazing how a few tweaks can help with naps