In short, indestructible removal doesnt try to kill the creatureit finds another way to take it off the board or make it useless
A playgroup of friends has pre-established rapport between its players that usually lets people get away with more shenanigans, so showing up with a bunch of silly effects that derail games would be much less likely to end with someone picking up their cards and leaving in a huff
However, it has massive impact on a few matchups
Aside from being a human, which is a very relevant creature type in Commander, Modern and basically every other MTG format, Esper Sentinel is good because it reads: Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays X, where X is Esper Sentinels power. Its a bit like Rhystic Study, but the cost can be far higher if youve got things that make humans stronger or you can put +1/+1 counters onto Esper Sentinel
Cards like Overlord of the Hauntwoods and Aftermath Analyst should help you get to that prerequisite in no time
Though this doesnt seem that impressive at first glance, bear in mind that, armed with a Rare Candy, you can evolve this Charmander into a Charizard ex on the turn after its played, then power it up immediately using the Charizard exs Infernal Reign