Their selection "process"[1] was.. not what I'd choose to use, especially since they changed the priorities as they evaluated. But then they abandoned that process[2] so I wouldn't read too much into the evaluation.

Basically as far as I can see, the main reason BlazeGraph was chosen was this: [they] had me out to their office (a house an hour and half from mine)[3]

I'm sure BlazeGraph is fine. We were doing a very similar evaluation at the same time, and the Titan situation screwed us over too. But we took a look at BlazeGraph after Wikidata chose it, and found it pretty rudimentary at that time.

[1] https://phabricator.wikimedia.org/T90101

[2] "As you can also see we didn't finish filling them all out. But we've still pretty much settled on BlazeGraph anyway. Let me first explain what BlazeGraph is and then defend our decision to stop spreadsheet work" https://lists.wikimedia.org/pipermail/wikidata-tech/2015-Mar...

[3] https://lists.wikimedia.org/pipermail/wikidata-tech/2015-Mar...