Yeah its typically rare but there are examples of champs in the past who got nerfs designed to maintain high elo power while nerfing low elo power this is typically because lower elo players dont/can't counter the character with higher level mechanics or is/are too safe to play at low elo. Hence nerfs design for low elo.
There's only one character I believe was strong in the high elo which was weak in low elo, mostly because the champ required high-level mechanics/teamwork to function properly in which high elo hes strong but low elo weak because of a lack of teamwork
I don't play DOTA/Smite/Lol but HoTs. But the situation is similar.
Mind you, that there's buffing stats, and reworking heroes/champs. As i said previously, low ELO changes should be focused around useability/gameplay wise. There's also a misconception on low ELO as well. I'll say there's bottom of the floor low ELO and "normal" low ELO. While a MOBA has an easier entry level, there are still people who are there just to smash buttons. RTS have a higher entry mechanic wise, but if you are at the bottom 30%/50%, there are other problems rather than balance.