I'm so glad to see this topic being discussed by a prevalent hobbyist youtuber. I've always believed a lot of people are overly stringent on what fish can be kept at exactly what temperature. You may or may not agree. Check out Aquarium Co-ops video about (usually) not needing a heater or needing to be constantly precise with temperatures in the aquarium. You may or may not agree but the video is worth a watch. It's pretty much been my school of thought throughout the years in the hobby.