Pathfinder games also have insane amount of options and complexity to them. DnD 5E is much more accessible, you don't need to read through 100 feats in character creation.
If people find these games too hard without a min-maxed party, they should just play on the easiest difficulty instead of asking for a bigger party size.
But the request for a bigger party size has hardly anything to do with difficult management, so this is a spurious argument.
And even the common rebuke "You can more or less get on with any party composition" is super-weak, because the point isn't "getting on". It's covering a vast range of options.
I WANT a larger and more diversified party not because I need it, but because I enjoy several aspects of it:
- benefitting from a large variety of different loot (rather than spending half playthrough going through "Oh, here's another mace/heavy armor/pole weapon/spell/magic-item-with-a-weirdly-specific-bonus that I will never have any use for").
- Enjoying the freedom to include hybrid/suboptimal classes without having to kick out a proper "mainstay" from the party for the sake of experimentation
- Accessing and going through MORE companions quests at any given time.
- being more reliant on broad planning than on lucking out the RNG on every micro-managed action.
- Feeling more comfortable in "rolling with the punches" with the occasional failures, rather than being compelled to reload as soon as things go south.
Etc, etc.
Of course, once again none of these arguments is NEW, because as usual they are answers to the same old tired objections people already did in the past.