Critic at Bloomberg calls NBBJ's Gates Foundation building bland...

Artifacts from many countries hang on the wall and strategically placed screens play videos of work being done, but they are background ambience, not front and center. The place is almost aggressively impersonal, as if any meaningful architectural gesture might offend someone or be read as colonialist bullying.
A visitor center will open next year, but it’s conceived as a museum, and may feel like a defense against interested citizens rather than an invitation to them.

The default to blandness is a lost opportunity.

Blame for the blandness? Probably all involved: the clients, the firm, and the city itself. Seattle knows lost opportunities like nobody's business.

The building appears to be a mirror of our town. For example, what do we see in the future visitor center: "...it’s conceived as a museum, and may feel like a defense against interested citizens rather than an invitation to them"? If you live in Seattle, you will recognize this instantly: It's the architectural expression of being passive–aggressive.