Be mad at ESPN for a lot of things, but not this. Because the game was on Stanford’s home court, PAC 12 Network has first rights to it... ESPN could’ve picked it up (and likely would’ve) had they denied it. Same for Baylor, if the game was on their home court, FS1 likely would’ve picked the game up and if they didn’t, then ESPN would’ve picked the rights up... so if there is anybody to blame, blame the conferences for not aligning themselves with a network that can broadcast nationally.
Another example, South Carolina plays Purdue tomorrow AT Purdue.. Big Ten Network has first dibs, but turned it down for whatever reason and even then, I believe BTN is affiliated with FOX, so that game still could’ve ended up on a Fox network... but anyway, ESPN negotiated and picked it up and that game will be on ESPN2.
Closer to home, I believe SNY has some kind of dibs on UConn games, but those few games that are shown on SNY (usually AAC Conference games) are blacked out locally on ESPN but may be shown nationally on either ESPN’s linear OR non-linear network (WatchESPN/E3).
This also explains why you don’t run into these issues of being unable to watch a game with UConn/South Carolina/Louisville etc.. (ACC/SEC) schools.. because through their regional networks, ESPN has first dibs on those games and they’ll always take the big games from the SEC Network, the ACC Network (not linear yet, but ESPN has long had priority to ACC games) or SNY and place them on their national linear networks. ESPN doesn’t have that power over the Pac12 or Big 12 (minus Texas).