I don’t know why relative humidity is used for laymen. I remember when I learned the Dew Point is what you can use to gauge what it feels like. I grew up in the South and later in life moved to the northwest and people would say it was humid sometimes in the summer and could never understand why they thought that. They’re just looking at the relative humidity on the weather app or whatever. Whatever the RH is if the dew point is 70°+ it’s gonna feel way hotter.