You have a habit of taking a point in isolation from the context and debating it in a whole new context in order to say things that sound convincing but aren't really relevant to the original point, please stop. Interrupting rests was something that used to be possible & used to make a big difference in things like the rate of HP recovery, but 5e provides tools like r
itual improved force cage & instant fortress on top of rest rules that make actually doing so rather pointless.
And you have a habit of ignoring the fact that many parties
don't have access to these things. As I mentioned elsewhere recently, in the five games I'm playing or running, there's a grand total of two wizards (only one of whom is even high enough level to cast
tiny hut) and two bards (one of whom is multiclassed and so way behind on the spellcasting).
You're also ignoring what can be done with a
tiny hut. Yeah, the monster can't enter it. But they can surround it and lie in wait, lay traps outside of it, kill your horses (which you can't bring inside), or leave creepy notes outside of it (did that one once, to great results--they couldn't decide what was worse, the note's threats or the writer's terrible spelling). And there's
no way for the PCs to do anything about it without dropping the
tiny hut or leaving its safety.
You're
also ignoring that bards get very few spells and, outside of those two free spells wizards get each level, DMs have total control over what spells a wizard gains access to. If you choose to drop a scroll or enemy's spellbook and it has
tiny hut in it, the blame's on you if it wrecks your long rest encounters. If a wizard or bar wants to give up one of the few spells they can actually pick each level in favor of taking
tiny hut, then that means they're not picking up a spell that's useful in other places. That's the trade-off.
This is not a situation where you can simply blame the dm for 5e's bad design because the lack of lethality & triviality of recovery in 5e still provides the gm with little room to provide magic items & cool toys with mechanical impacts on survivability, combat effectiveness & recovery.
You keep saying this and I have no idea why. There's absolutely nothing in 5e that prevents you from putting magic items and "cool toys" with mechanical impacts in the game. As a player, I have found or purchased magic items. As a DM, I place a fair number of them.
Let's see... one of the paths I'm working on is an almost complete redo of the Amber Temple in CoS, since I don't like the actual adventure location in the book. I'm counting 19 magic items of various levels of power
. A couple of the items have curses of one degree or another, and many of them are creepy enough that my players will almost refuse to do anything with them besides maybe destroy them with fire (such as a
circlet of blasting that looks like a bronze crown studded with human teeth). My players have a weird aversion to searching bodies, so they will likely miss several of the items as well. But they're there. And nothing in the DMG is forbidding me from placing these items.
Of course, the monsters include a fair number of high-CR fiends and undead, and the party has no cleric, just a paladin.