To be honest I don't really see a lot of value in doing that. I think it's rarely needed, if ever. You can see overall downvotes on your profile so you'll most likely know if you got a downvote recently. Mods can see who upvoted and downvoted so that helps detect spam and such.
If you're really desperate to know if a particular post received a downvote you can ask a mod in chat to check it for you (as long as you're not bugging them all the time to check things).