This Rule Sucks: Legendary Resistances

So my players fought The Tarrasque recently and I felt for my bard's player. He spent the first three quarters of the fight burning through the legendary resistances, then cast Otto's Irresistible Dance, which would have been an excellent strategy, if it didn't count as a charm effect, which the Tarrasque is immune to (I have an issue with immunities also, but we'll look into that later). His last few spells were resisted due to the Tarrasque's "advantage on all saves" effect.

My monk's player never landed a stunning strike, The Tarrasque never got stuck in the wizard's Mud to Rock spell, and so on and so forth.

Saving throws in general are just a reversed version of how attacks work in Dungeons and Dragons.
For regular attacks you have:

The attacker rolls a variable attack roll on d20 + modifiers =/> a static defense number (Armor Class)

For saving throws you have:

The defender rolls a variable saving throw on d20 + modifiers =/> a static attack number (Save DC)

Mathematics-wise, they are exactly the same thing. Some players seem to prefer attack rolls as they get to roll the shiny math rocks, and don't like saving throws as someone else is rolling the dice.

So saving throws are just attacks, expressed slightly differently. Now imagine you're attacking an orc and you roll a critical hit. You start to cheer, only to have the GM go: "Nuh-uh, he dodged".

When I was a kid and would play make believe, there was the one kid, you know the one. You shoot him with your laser, he has a laser proof shield. You shoot him with your machine gun, he has a bullet proof shield. You cast a spell on him, he has a magic proof shield. You hit him with a billion trillion infinity double gun, he has an everything proof shield.

That kid grew up to work at Wizards Of The Coast and he designed legendary resistances.

That's not really fair. Legendary resistances are an attempt to keep the big boss fights feeling interesting, if they didn't exist, players would spam their crowd control spells until something took hold, and then bypass the fight. But I always feel like the kid with the everything-proof shield when I use them, as i'm effectively just going "nuh-uh it doesn't work!" when the player has already succeeded.

The other thing i've always noticed with Legendary Resistances, whenever they're used at the table, the other players always console the player who's spell or ability got legendarily resisted.
"No that's good, he's only got two left now!"
"Good job, we've got to burn through these fast."
The very fact that players need consolation for burning through Legendary Resistances is proof to me that they are unsatisfying. Nobody ever needs to be consoled after rolling a critical hit.

So how do we make this more satisfying for players? Two options sort of stand out to me. One is from the truly excellent blog goblin punch which none of you should go look at because it's far too good and I don't need to be living up to those sorts of standards.

My first idea is to simply keep Legendary Resistances, but make them take a round to come into effect. You put the dragon to sleep. For 1 round. Then it wakes up. Simple, but I could see it completely invalidating Legendary Resistance as keeping a boss out of the fight for a whole round multiple times could make the Legendary Resistances effectively pointless.

The other solution is from goblin punch, and it's pretty simple and elegant. He calls them ablative saves, and it works like so: the boss fails a save, but chooses to resist. He then takes a flat 10 or 20 damage. Goblin Punch is an OSR blog, with much lower hit point totals than fifth edition, so I would simply tweak it to:

Legendary Resistance:
When the creature resists a spell effect, it takes damage equal to the spell's level times 10.

This means that you can still burn through with low level spells, but if a high level spell, gets resisted, it provides the consolation prize of a bit of damage.