It says on the wiki
"The provisional name is a misnomer, as there is evidence of an identical-looking linear version"
You are 100% positive that every single switch is perfectly linear? Although I've found a fair amount of evidence in favour of linear Futabas, not everyone agrees with me on this, which is why I'm keen to prove beyond reasonable doubt that a linear one exists.
Normally I'd suggest you open one up for inspection, but these switches don't come apart :-) It's a shame that you didn't find a busted keyboard, as then there would be no harm in sacrificing a switch to prove 100% once and for all that the linear version exists, and what exactly is inside one of them.
And yes, then we need to rename the stupid things. jacobolus dislikes my choice of "SMK second generation", which makes me wary about using "Futaba second generation". I agree that this is a dubious choice, since we can't prove the absence of intervening or preceding product ranges; for example, HaaTa turned up some amazing old Alps switches from way back when, long before the ones we all know and love.
Unfortunately I really suck at naming things (all my switch names suck) but unless anyone out there can do any better than me at contacting Futaba for details¹, we'll need to make something up.
¹ Companies on my no-reply list include: Alps, Forward, Futaba, NMB (USA), Sejin, Mitsumi, Wong's Electronics; companies on my awkward and uncooperative list include: iRocks, MacAlly, SMK, RAFI, Ortek, Printec DS — all companies who the right person (especially Japanese, Korean and Chinese speakers!) might be able to coax more out of. I was hoping that tinnie could tackle Wong's as they're a Hong Kong company. So much we still need to learn and knowledge is being destroyed every year as more tooling and documentation is discarded, staff leave, and companies close down. Native Asian language speakers are key to this, I feel, but over at Deskthority I've failed to find anyone willing to help with anything.