I appreciate seeing Egan brought up.
I've always felt he was overlooked by the masses as the father of "stuck in the machine" popular sci-fi of the 90's (13th Floor and The Matrix owe him much recognition). In the past couple of years, a couple of really good sci-fi games (Talos Principle and SOMA) have come out that explore these topics and, unfortunately, I read/hear comparisons to these movies and not the deeper source work of Diaspora and Permutation City.
As a philosophy dropout turned IT consultant back in the early 90's, Egan's concepts have provided decades of thought experiments (and as someone with a few mental health issues, an existential crisis or two that teetered on outright psychotic delusion).
I wish I could still read fiction. I've missed his last two works but I continue to love his ideas from afar.