[broadgage]

I consider it possible that very old valves with mis aligned electrodes might have been made like that.
Such "B grade" valves might have been sold at reduced prices to hobbyists, experimenters, researchers, or to staff at the works.
Such valves might be more likely to have survived 80 years or more in "great granddads workshop" than a heavily used perfect example.

Or they might have been dropped ! under certain conditions the forces thus resulting could bend internal metal parts out of shape but leave the envelope intact.
I have observed electric lamps that have been dropped and the filament thereby displaced. Such lamps often work fine for say room lighting, but would perform very poorly in a sophisticate optical system.

In the case of very early valves, design and manufacture were less well understood than in later years, and more empirical than scientific.