Yes, Gibson does screw up their acquisitions on the regular. But they should be given a pass on the Studio Vision thing: I know that the entire Internet will, when searched, turn up a thousand references to "Gibson killed Vision," but that's not entirely true.
In those days, the evil Henry J. was already running Gibson (he bought the company from Norlin in 1986). Henry's most notable aspect is his resume: he worked for Delco before becoming, essentially, a member of a corporate raider firm. So Henry J.'s personal foundation is not as a guy who builds guitars (although he does play one), but as a guy who buys companies to do one of two things: rescue them, or grab a specific piece of IP and leave the rest to die.
There were really only Opcode and Mark of the Unicorn in those days, and MOTU's product development and engineering chops were superior. Opcode was on the ropes when Gibson came along, with the intention of saving the small company with a big infusion of cash. They gave Opcode operating capital and some marketing expertise, but it was too little and way too late. Opcode died not because of Gibson, but in spite of their efforts. (And I ended up choosing Performer, and later Digital Performer, because I'd heard Opcode's fat lady was warming up in the wings.)
An aside on Trace Elliot: those were awesome amps, but they didn't have the brand power to compete with the Bigs. And when Gibson bought them, they did the unexpected... they didn't change a thing about them except the badge and the Tolex color, and renamed them as Gibson Goldtones. The Goldtone that was previous known as a Velocette was a killer amp, and with Gibson's backing would have sold huge if they had left one more thing alone: the price. Henry apparently felt that Gibson's name was worth a few hundred bucks more. Buyers disagreed. Another great product out to pasture.
Now, with Tascam, I suspect that Henry simply decided that buying TEAC to get the digital recording expertise they wanted was both cheaper and easier than developing their own. He was wrong on both counts: buying TEAC was way more expensive than a team of rock solid DSP engineers would have been, and the acquisition only seemed easier to Henry because that's what he knows best. Anyway, I fear that he doesn't give a rat's behind about making a profit from TEAC. He just wanted to make some guitar cables that would record everything you played through them.
So, to wrap it: Gibson didn't kill Vision, even though everybody thinks they did. But when Tascam is in its grave, everyone will say Gibson killed them, and I think this time they'll be right.