tldr: villagers with professions don't breed in 1.14.3, or they are reproducing extremely slowly (not reproducing in 24hrs) while unemployed villagers breed just fine. Is this intended or a bug?

detailed:

I've been struggling with my villager breeder since the game update from 1.14.2 to 1.14.3. The design was simple: get 4 farmers up in the sky, get a lot of beds and trick the baby villagers to fall through trapdoor down to a collection pool. In 1.14.2 this works very well, I can get 1~2 villagers per in-game day. But in 1.14.3, the design was broken, that I've waited cumulatively 24hrs and still there's no breeding. There are occasional heart particles (most of the time only 1 villager is in mating mode, sometimes there are a pair), but still no baby.

I searched a lot and tested many possible causes, and found out that the employed villagers such as farmers cease to breed, even though there's more than enough beds and they can pathfind to them (they can sleep on them), they've been tossing food at each other like crazy, no villager death, etc. But on the other hand, unemployed villagers breed just fine and as quickly as in 1.14.2 (roughly 1 per pair per day), as long as they have food. Same in both my survival world and a creative world, and same in naturally generated villages. 

I further found I'm not the only one who noticed it: https://www.youtube.com/watch?v=96kHEzbiumI. But I don't see it's been reported here. I assume this is not a feature and is not intended, right? Otherwise this "feature" doesn't make much sense.