Just thinking out loud about what the cost of expensive material components actually says in the overall story of D&D, and what happens if you tinker with some of those assumptions.
In my gaming history, ever time I or any other DM has gotten the players to agree that “THIS time, I swear by Boccob, that we’re gonna pay attention to material components!” it only lasts for a session or two and then we all forget.
Right up until someone “keeps casting” a spell that the DM thought is messing with the game and then the DM would say, “Do you have the components to cast Identify that many times?” Which would usually end in an argument and a promise that “Ok, fine. We’ll let it go this time but NEXT time we need to remember components.”
And thus the circle of well intentioned, but universally ignored, bookkeeping began again.
As in all things, your milage will vary. We use material components. I’m not going to say we’re prefect at tracking, but pretty good. I think it can add to the game, so long as people are into it.
We did one game where someone had a bunch of old blank pogs that we just wrote what the materials were on them and through them in a bowl to cast spells.
The spell casters would sometimes get distracted by playing Pogs
As a group my players are hit and miss. Some of them are very good about looking for and acquiring the costly and or rare components. It’s funny but my biggest rules lawyer never thinks about needing to have any of the special or costly components written down. He plays the Wizard, so I will often ask him about the more rare components.
I think in 5E the components are an important balancing point for casters and big game changing spell at higher levels.
MOST of the time, it’s a matter of “is it rare/ expensive” and/or “do you have your gear”?
If there’s a fight in the middle of the night, and the mage grabbed his staff and ran out into the night, you’ll have to go back for your components. If it’s rare, I think you know what I mean.