It seems obvious to me. Think about it, what's the only type of motorbike in the world that KTM doesn't already have a very strong place in the market?
Answer: trials bikes.
Acquiring GG (I know, they didn't technically acquire them, but at 60% ownership, they may as well have) allows them to jump straight to the front of the line with very competitive trials models, with lots of history and expertise. A little tweaking of a few technical details, manufacturing processes, and management practices, plus some of the KTM mothership's marketing budget to promote them more, and they'll be seeing an ROI on this deal in a hurry. 100% business decision.
That's what this is about. Which isn't entirely a bad thing. We will almost certainly see strong, competitive, updated trials bikes for the foreseeable future. While some of us certainly won't care for them being tainted with orange blood, it looks like this was better than the alternative of closing up shop forever.
The big downside I see in this is that the enduro line won't likely survive. Husaberg brought a lot of technology to the table to a young, unknown KTM. Husqvarna brought fantastic name recognition, and a great opportunity for KTM (now well established) to brand and up-sell a "premium" bike. GasGas enduro brings nothing of this sort to the table, and if they're not able to differentiate it substantially (not from a technical standpoint, but from a sales standpoint), then they'll kill it.
The only way I could see it working, is that if Husqvarna is the premium brand, GasGas could be the budget brand that competes with the Japanese bikes' price points (or maybe the other cheaper Euro bikes). That said, they'd have a veeeeery fine line to walk to avoid cannibalizing the sales of their higher priced (and higher margin) orange and white bikes. While I as a consumer would love to see a model lineup like this, I doubt seriously they'd actually do it.
Either way, I wish all at GasGas the best of luck, and certainly hope to see them prosper over the coming years in this new relationship.