Dogged by controversies throughout its lifespan, do you consider the Xbox One to have been a good console at the end of the day, and why/why not?

No. Lacked in power. Too expensive. Half bake promises that they never delivered. No exclusives that were system sellers. If you wanted Halo,Forza and Gears, a decent PC did you fine. I was able to play some stuff on a 1060 Laptop at the time. MS admitted they fucked up and lost to Sony for getting people as digital libraries grow and carry over. 

I think so. It was lacking in exclusives, but it delivered on features. It played CDs (as the only system that gen), DVDs, Blu-rays, 4K UHDs (as the only system that gen, but only on One S and X). It got backwards compatibility with Xbox 360 and og Xbox, to some extend. Play anywhere was a great feature, now it also got disc-to-digital, where it can even be used to digitise Series X games.
The price was competitive (except ar launch). It gets support to this day 13 years after release.

Short answer: no
Long answer: it sucked