(Author chiming in, you've given me an opportunity for one of my favorite sport-arguments)

I'll admit that even Jean-Louis Gassée (Former Mac head, Be founder) later said NeXT+Steve was the right choice (see: https://9to5mac.com/2011/11/11/gassee-thank-god-apple-chose-... ) - though he said it for personal reasons based on his contempt for Apple's management.

Some not-carefully-composed points of argument that Be might have been the right choice, because I like doing it for sport:

BeOS was truly a ground-up creation, OpenStep was a Display PostScript environment largely licensed from Adobe running on a hacked-up Mach with some BSD pieces pulled inside the kernel boundary to make performance acceptable (this is XNU, the kernel Apple still uses in everything). That had two points for Be - Apple had to replace the whole display layer, partly for licensing cost reasons and partly because developers weren't interested in dealing with the "Yellow Box" OpenStep API or being stuck in the "Blue Box" legacy compatibility jail. Equally or more important, BeOS was vastly more performant on the same hardware - doing the "the UI stays responsive while I'm playing a dozen media files back on this shitty Pentum MMX" stunt was always a blast around the turn of the century. BeOS was also naively SMP with a nifty and mostly pleasant thread model that has some advantages (and annoyances) over the dominant event loop way of things, but always remained responsive, while Apple inherited the spinning beach ball from NeXT.

For another big technical point that history actually agrees with me on, OpenStep used a passable UFS implementation (that Apple reverted to HFS+, which was already getting long in the tooth in the late 90s, apparently largely because Adobe wouldn't get their shit together to make their products run on a case-sensitive FS...), but BeFS was lovely in ways we're finally getting elsewhere 20+ years later - exactly so in fact, Apple eventually hired Dominic Giampaolo who designed BeFS to design APFS, and it really shows.

BeOS was also already suited for semi-embedded applications, both in various commercial multimedia gadgets, and also the BeIA internet appliance stuff. Since the bulk of modern NextStep-family devices are phones and tablets, there's no reason to think a Gasse/Be Apple wouldn't have thrived in this environment (I know, Palm borrowed Be parts for Palm OS Cobalt and didn't do well, but maybe they were already doomed by that time).

Also, Be was _profoundly_ personal, looking toward a "everyone has their own WebServer running their personal services" kind of future, rather than the "Everyone back into the ~~mainframe~~ major cloud provider" future we got, and I can't help but thinking having one of the big industry players not in the roach-motel platform game would have been good for society.

Jobs did in fact use a ThinkPad running OpenStep/Rhapsody builds around the time of the NeXT-buys-Apple-with-Apple's-Money situation. It was a 560 (not E), there is a NextComputers forum thread about it where Marc J. Driftmeyer who set up the machine Steve had at Macworld '97 talks about it http://www.nextcomputers.org/forums/index.php?topic=457.0 .