Werebat
Explorer
This is not true!
You stop doing anything strenuous. That is 'resting'.
If you do anything strenuous within one hour then you didn't get a short rest. If you avoided strenuous activity for a whole hour then you did get a short rest!
If, in the previous 8 hours you have had at least 7 hours free of any stressful activity, then you have had a long rest.
There is no logical or RAW reason to imagine there are two different kinds of 'not doing anything'.
Arial Black, if this is true, then is it not possible for the DM to pull a "gotcha" on PC wizards and keep them from getting their spell slots back?
It's been two days since the last combat, then there is a combat in the evening where the wizard casts spells, then the wizard wants to long rest and the DM smirks and says, "No no no, you only get ONE Long Rest per 24 hour period, as per The Rules -- and you had your Long Rest just before the combat a few hours ago!"
I mean, the temptation would be THERE, if the player had a habit of rules lawyering for advantage in the past. Theoretically.