Librarian Villager continue trading if the trade limit is reached.
I don't know if other professions are affected too.

I tested it again and was not able to reproduce the issue.

I use a datapack in this world but it only adds one crafting recepie for glowberries and one for moss blocks.

Edit:
World download
This world was originally created in version 21w08b. (Default settings)
The video was recorded at:
/execute in minecraft:overworld run tp @s 686.52 59.00 -762.50 265.35 15.30