People keep 50cm wolves with cardinals, doesn't mean you can put cardinals with wolves. Same applies here. It worked for you, it's still not healthy, and prone to develop fungus on your channas. No myth here.
I've also had my tanks hit those highs during the warmest parts of the summer I try to keep them cooler and recommend it when possible but They can withstand even thrive in those temps for warm summers , just not year round.
If you weren't cooling them for winter you'd see that after several months at high temps they'll go from being vibrant and active to dull and lethargic. After about year they melt away with a sudden fungal/bacterial infection . It happens very fast and typically by the time you spot fungus it's much too late it seems almost as if their immune system just fails on them .
okk bro , winter starts here now the temp is going down to 20 at night , in November December and January it goes down to 10, in summer I place them in cooler ,from April to july
its winter time in India ,, the temp is below 18 in night , but still my stew and bleheri demands for food everytime I go near them , how I feed them now , once or twice the week,