Even if some of the IPs and complete exclusivity would help Nintendo, I doubt Nintendo would buy them anyway. I'm quite positive Capcom is worth a lot and Nintendo, even with their large assets and money in the bank, wouldn't be willing to shell out some serious amounts of money for one company that has several of it's own problems.
If this was Capcom selling off their IPs then it would make perfect financial sense. However, this is a stock takeover of a company and I'm pretty positive that's the harder route. It could work out, and I don't agree with looking purely at worst case scenario, but there are drawbacks.







