@15gb2 With my first, I had no sense of schedules or wake windows and breastfed on demand. He slept great at night but naps were extremely difficult and going by "sleepy cues" ended up with a lot of rocking, false starts and days where he barely napped at all. Around I think 6 months I tried the 2-3-4 schedule and it worked immediately. Consistent naps with minimal help. I think I was missing his cues (or he didn't really have any) and offering naps at the wrong times, when he either wasn't tired yet or was overtired. It wasn't so much imposing a schedule on him as figuring out when he was actually tired and wanting to sleep. When naps would get difficult for several days+, I would look up if it might be time to drop a nap and change the schedule and then do trial and error on it.
With my second, I did a lot of contact naps for the first 4 months, but by 12 weeks I started trying out a loose schedule based on wake windows. I never made him sleep, it just helped me know when to TRY to get him to sleep. It was a huge benefit for my mental health because I wasn't spending hours every day trying to get him to nap at the wrong times like I did with my first. After 4 months we kept the schedule but transitioned to crib naps. He still has a pretty consistent schedule now at 10 months.
With my kids, they seem to be on the higher end of sleep needs. They don't really nap in the car well and don't do well if we move or skip naps. It makes things challenging at times, especially if the naps aren't at convenient times, but it works for us. The stress of having a tired baby is worse for me than being stuck on a schedule.
For feeding, like I said I breastfed my oldest on demand as you are describing and I fed him constantly for a long time. I think it was messing with his nap routine too. With my second, he was bottle fed so I had to track ounces for pumping and feeding, but I wasn't feeding him constantly. I tracked sleep and feeding for both in the same app so I can compare them easily. I really think for me, on demand feeding without tracking, feeding to sleep and having no sense of when to attempt naps made things really stressful and made that time really hard for me. Having a more consistent schedule later with my oldest and then early on with my second seemed to make things a lot better both for me AND for the baby.