The "single player game doesn't need balancing" argument is talking about overpowered mechanics being rebalanced so that they are no longer overpowered. This is unnecessary because the game is not competative and players can (artificially) limited themselves to not using those mechanics.
Overpowered, by definition, means OVER powered. If the mechanic is OVER powered, it's a problem. If you admit that a certain anything in a game is OVER powered, you're admitting it's a problem.
What you want to be arguing is that you don't feel the resistance issue is too powerful for the game and explain why it doesn't make the game worse. An important part of having fun in a game IS an appropriate challenge to most people. An argument of "Sure it's overpowered but people can just not do it" isn't a productive one- especially when it's relatively easy to /accidentally/ get ludicrous +Resistances.
My personal argument shall remain that resistances were too good, but a hard cap that denies permanent immunity to /anything/ gets rid of a big chunk of fun to be had and causes a big dissonance when you've got single suits of armor giving 70% resistance to something by themselves.
