YES, and this became an on-again off-again obsession. I'm not a plane collector but it was fascinating how nice planes can become.
In one case it was a matter of tightening up a mouth on a cheapo plane, which did help:
https://forum.shopsmith.com/viewtopic.php?t=5569
In another case an old Great Neck Corsair became a
much nicer working plane than a late-model $20 Stanley. This was one old plane that did have some bow to the sole when I got it. I mainly used a 12" SS Sanding Disk to take down the high spots, then I went to manual sandpaper sheets on a flat piece of glass. I read lately somewhere that a guy likes to use WD40 on flat sandpaper for quick truing jobs.
https://forum.shopsmith.com/viewtopic.php?t=4161
Later in that same thread I made my own wooden plane, which was a joy. And all I used to true its sole was another plane (no jointer, no belt-sander, etc.)
Most recently I went all out to make an infill plane from scratch.
https://forum.shopsmith.com/viewtopic.php?t=5799
I've read a couple of books on planes and I find them fascinating.
Besides general truing, smoothing, etc., sometimes for very small wood pieces I will put my Plane upside down in a vice or a workmate, and use it as a jointer.