They bought their minority stake in BAMTech (the streaming spinoff of MLBAM) earlier this year. There’s no way they’re going to mess this up from a tech standpoint either.
HBO Go was totally redone from the ground up by the MLB team I believe and there were some hickups at the start but it has been pretty good since then.
Minor correction - HBO Go is still in-house at HBO. BAM runs HBO Now, the OTT service.
Source: I work at BAMTech.
HBO Go might be okay (I've never used it), but it's a rare day that I can watch a full episode of anything on HBO Now (Xbox One) without "We're unable to play this video right now. Please try again later". Netflix is the only streaming service which has performed flawlessly for me over and over again. You'd think it was a solved technology problem by now, but Amazon, Hulu and HBO Now still seem to have playback issues for me on a semi-regular occurrence.