hmm. I hard to see why Blockchain advancements will impact M&A unless I am missing something. Only thing to consider is potential payment in bitcoins and how would that impact transactions or even valuations. Even then, if crypto can replace currency it should still be swappable ignoring the volatility of the currency class in itself
I think the underlying technology, specifically smart contracts, could have the biggest impact from reducing pre/post closing costs and possible legal/regulatory/trust impacts.