The average user can’t be expected to remember all of the commands needed to use their regularly used programs

They were expected to do so for decades, or they hired a computer (as in a person) to do it for them ($$$).

the terminal could be used to reformat storage devices, but MintStick essentially replicates the Windows GUI for doing it

Depends on what you mean by "doing it." I'll look in a second, but from the name and your description I'm guessing it's got parted/mkfs.xxxx/dd and the lot installed on it, maybe something for dealing with boot sectors or GRUB. I'm also guessing that behind the scenes it's just using a GUI to build up the command line behind the scenes, and I like that style of GUI.

The more users Linux has the more resources it will get.

Concur.

For power users, nothing stops developers from also maintaining terminal support.

UX design/GUI development isn't entirely orthogonal with backend core program stuff, but they're close. I'll argue that you're better off starting with the core stuff and save the GUI for later.

I looked at the mintstick code. It looks like it's using python to pull down some OS image from the internet and burn it to a USB. I'd rather just stick to the way I know :-) I didn't know python had a parted library, so that's new.

I am all for more people knowing how to use a computer, but I'm also in the camp that I ate the learning curve enough years ago that I don't want to give up my ways. I don't expect everyone to want to master the terminal, but I won't give up the power in favor whatever a GUI designer chooses to implement. The trade isn't worth it to me.