SP potions are fuel for the tools. The tools are the spells. A better analogy over time would be changing up from the F9F Cougar to the F22 Raptor. Casters gained new tools. They didn't ignore them to continue alternating between burning hands and acid spray. SP potions would be the equivalent of reloading armament and refueling without stopping, and doing so repeatedly. The F22 can do a lot more with that ability than the F22 that cannot, making that ability very powerful. The Raptor with that ability would still be a big upgrade over the the Cougar and that ability would be more effective on the Raptor.
Also, a hammer in the hands of someone learning to use it is not as effective as a the hammer in the hands of the person who knows how to use it. Even tho I would consider the hammer a poor analogy changes to the person swinging it still makes it more effective even if it is the same hammer, similar to the changes going from a caster years ago to a caster now.
You need to feel over powered to have fun?
You are ultimate responsible for your own fun. Turbine is ultimately responsible for the enjoyment of as many players as possible. That can mean someone has to suck it up sometimes. Could be me, or you, or they might come up with something else that makes us both happy, who knows? But sometimes changes make the list of things to change and it's not always what we want. I've been hit several times over the years that way and I rebounded.
So why should a player be forced to roll a caster to do that then? If I follow the logic behind being able to play how I want when I want and the only thing I need to concern myself with is whether I have fun why would you expect me to be forced to play my caster to do it?
The reason SP totals exist in the first place is still because players are not supposed to have the options of simply having 200,000 spell points to throw down the throat of any mob he or she wishes. If that were the case he or she would already have those spell points, or spell points wouldn't exist in the first place, or spells would not be as effective as they are.
I agree potions are not limitless, but the limits themselves are slack enough to make the SP available to blow as more than enough and on a whim. I think that is counter-productive to the actual game design, mechanics in place, and actual intent. Those are also reasons to change it.
The reasons players say we shouldn't change it have amounted to:
1) you can't tell me how to play
2) i can blow threw SP potions if I want to
3) we need the money spent in the store (which, based on changes to make casting cheaper also indicator this is not a design goal)
4) what's it to you if we want to play that way
5) i'm responsible for my own fun
6) Matt should stop forcing his playstyle on others
7) because not many ppl are affected we should ignore it
8) players who do that should pay for improvements to my game
9) there's also healing available so if my thing gets change your thing should be changed take that you dirty melee
10) other player agree with me so i must be right
11) this thread is only awesome because i am here
12) etc etc etc
The change makes sense because:
1) it helps with balance concerns among players
2) it helps development balance content for players
3) it establishes a better expectation among the community on what to expect
4) it help ensure more players feel like they were able to contribute in place of watch one person who decided to join a group to show off how he can solo
5) it prevents players from spending plat or TP unnecessarily as they learn the game
6) it promotes learning conservation and tactics over brute forcing
7) it reinforces the existing game mechanics instead of bypassing them
8) spells have become cheaper and more effective over time
9) epics have cheap SP options and PrE's have cheap SLA's and echoes now exists
10) the devs have been moving in the direction of not keeping meta's going full tilt with the expectation players would use efficient options and meta's for a more expensive, inefficient burst; something players seem to resist but restricting SP potions follows that same direction
11) shrines are more plentiful and already provide an in game control mechanism that's easy for them to manage expected SP usage when they design quests making SP potions less necessary for emergency use
Following the thread the reasons for the change look more reasonable than the reasons against it.