Still happens to both baby and adult bees, although much rarer.
Was not able to record adult bees taking damage from solid walls, but have seen baby bees take damage and dying from touching solid walls (in my case, glass).
Can confirm that this is an issue. I too have farmers who wont farm, at all. They do not even wanna cultivate anything to begin with, so all I got in my villages are empty fields.
Still present in 19w44a. Saplings wont grow if there are blocks (excluding dirt, in which case it will teleport onto that block) above it.