For everyone but racers, the question isn’t “is 650b better”- it might be, it might not, but it’s certainly not a big enough difference to justify replacing a quality 26 inch bike.
And there are other disadvantages for the consumer, companies have thrown effort into 650b that could have gone on improving other products- for example tyre companies have had to redesign and re-release their whole range just to stand still, the number of decent new designs in the last year or so are tiny. And despite that there’s still less choice for 650b than there is for 26- there’s just 1 halfdecent hard-use mud tyre, for instance, and even that’s come after a winter of people making do with stuff you’d never choose if you had the choice of 26.
Shops have been stuck with artificially obsolete stock and the need to buy in new stock that is basically identical in order to sell it for the same amount.
Wait, what? Are 29ers no good now then? What was MBR’s original position?
Nah, for ages they said they were rubbish. Then something happened to make them change their minds. Jury’s out on whether they just discovered they were wrong, or, it may have coincided with Specialized going all 29er 😉