I'd need to look a little closer but if ARM's P/E is lower than Apple's (which is v.high something like 15x trailing earnings, which for a billion dollar company is high) then ARM is actually dilutive and hence value destroying, for Apple shareholders.

I think the more relevant data point is the FTSE and DOW's bad week/month, and traders desperate to find any good news.

Whether or not the deal strategically makes sense, Apple need to consider it's impact on shareholders.