But as we've seen, as time goes on, people want to push 5e in different directions. Sometimes radically different. As for Mearls and Crawford's differing opinions, it comes down to this- if the party faces less encounters, yes, things are easier for them. But, and say it with me now, they gain less experience points. Now some people may have stopped with xp altogether, as is their right, but if you're tracking these things, the easier the game is, the slower it advances (and presumably, takes longer to reach the high levels that cause problems and become harder to run for).
On the other hand, if every game session is hard mode, you should get more xp, shrinking the the campaign, and more rapidly getting to the levels where power is problematic. As in all things, that means there should be a mix. Most sessions should not push the party to the limit, but a few can.
So all they're saying is, if you want a mathematically precise game, 1 long rest and 2 short rests per diem, with 6-8 balanced encounters will make your party run out of resources.
Change these numbers, and how long this takes changes, no real surprise.
So, TLDR; there is no wrong way to play, find a balance that works for you and your group.