I hope that Hayter is going to be Solid Snake in future installments and that he was not included because Kojima wants to move a in a different direction specifically with regards to Big Boss.
However, it's kind of shady that David Hayter had to get the news through the media and not directly from Kojima or whoever takes care of that within the Konami/Kojima Productions. If Kojima is trying to go another direction for the future of Metal Gear as a whole and just doesn't see Hayter as a viable part of that ecosystem, I'll be pretty disappointed. Metal Gear is one of my favorite series and I credit Hayter as being a big part of the experience that has impacted me so.
Still, if someone were to hear Solid Snake's gruff voice for the first time, they might find the acting a little campy/borderline cheesy. I am not trying to be flamebait here, but as much as I enjoy Hayter's portrayal and can't separate his voice and Solid Snake's visage, if Kojima is trying to make this bigger and closer to Hollywood standards level of voice acting and production, he might perceive Hayter's voicework as somewhat silly for a new audience. Hope that's not the case, but if it is, I get it.







