I live in Florida. It gets into the high 90's with 80% humidity. At the same time NYC is in the 80's with 50% humidity.
There are places that just aren't walkable certain times of the year.
Because we built them to be unwalkable. We ripped out the trees so there's no shade. We paved the soil so we could drive portable furnaces over it. You're not wrong that it's unwalkable where you live - it is also unwalkable where I live. But it not just because of natural climate.
96 degrees and 80% humidity is a dew point of 89. The highest verified dew point ever recorded in the US is 88, and that was in Minnesota which might sound odd to people who have never heard the term "corn sweat".
But yeah, even high 90's with 65% humidity (dew point in low 80's) is not healthy to be walking around in.
As you said, still not walkable :).