Soon as Multiplay is added to the equation that argument starts to falter. It is however completely valid in a single player aspect, you aren't competing in any direct way.
Sure you can just not use mods you find OP in SMP too, so it's not a real problem worth fixing.
But there is a problem of ego...
Just say I finally figured out how to run and automate a MK3 reactor that was self cooling and sustaining with a reinforced stone blast chamber around it 2 thick. You decide to show it off then you are met with a score of drivel from people with names that sound more like hashtags going [4TwennySwag]"Bro... Why bother with all that shit, just whack down a few ultis dude, you get more power and it can't blow up. You're dumb for building this man".
A bigger person would just ignore that but not everyone is that big.
That being said that's not actually a real problem, it just means it's harder to stroke ones ego with a minecraft mod. But it does explain why people find it difficult to just ignore things they find too easy, they feel like they are competing (Sometimes they are in PvP servers) with the other players and therefore feel forced to use the optimal strats. The mere existence of the easy mod trivialized what they are doing making the effort seem worthless.
Your argument doesn't make sense in response to SoB's.
On a normal server, you can easily not use mods you don't like. Don't like IC2? You don't
HAVE to use it. You can use TE instead. You can decide to not make machines at all and do only bees and farms.
On a server with Gregtech installed you can't
NOT use gregtech. That's what SoB's point is. Then you said something about ego, which has nothing to do with SoB's point. If people call you dumb for building certain things, then you're on the wrong server.
I don't really understand why this discussion keeps coming up.
If you like apples, then eat apples.
If you like oranges, then eat oranges.
There's absolutely no point or reason in arguing ad nauseum about "which is better, apples or oranges?"
There's a saying in French and it goes: "Les gouts ne se discute pas." "Tastes can not be discussed."
If you like gregtech, that's fine. Awesome! Use it in SSP or find a server using it, and play until your fingers are blistered and fall off if you want to.
If you don't like gregtech, that's time too. Don't use it in SSP or find a server not using it, and play until your ass is covered in boils and bed sores and you develop a severe allergy to sunlight if you want to.
You're never going to convince someone that doesn't like apples to stop eating oranges and eat apples instead, and you're probably doing something illegal if you do.