My experience with military gear is the opposite - it was designed to last long enough to use, with the recognition it’s going to be lost or destroyed in battle.

That, of course, depends on the item. Older stuff can be quite sturdy. For example, I have a 1960’s self-contained analog multimeter that’s in it’s own aluminum case (looks like it was designed in the 50’s, just post-WWII). It’s clearly been banged around (the case is rough) but it still works, and is designed to be regularly adjusted - there’s a sticker or label inside showing the last time it was adjusted.

It seems stuff from at least the 1980’s (probably the 60’s, really) had more of a “built just good enough” design goal. Regular/continuous maintenance isn’t much of a concern for the military as compared to us civilians.

That was an extra, I wouldn’t worry about it.

will depend more on whether Ryobi kills off the USB Lithium line like they did the Tek4 line.

This is where learning how to rebuild your own batteries cones in. Nearly all of them use multiple 18650 batteries, which cost about $2 each online.

I’ve rebuilt a few for my power tools. Larger ones cost about $10-$15 to rebuild. And newer batteries have greater capacity too.