It's easy to reproduce, place redstone torches next to tnt and it explodes, place it on tnt and it acts like the tnt is a regular block.
in the attached screenshots, the first 2 are in 1.14.1 and the last one, in the snow biome, is 1.14.2 pre-release 2
Pretty sure this is working as intended. Redstone torches don't power the block they are attached to. Try this with a lamp or something to confirm.