@Ange2 I think its core business as perceived by guests and most hosts is still personal sharing of space, whether a whole house flat or room in a home. That is its USP and what differentiates it from a Holiday or Premier Inn. it is also what opened up a giant market expansion creating accomodation that was not previously accessible... like my spare rooms which accomodate people who previously could not afford to travel as often for a weekend break or similar. I think that there is an argument for staying on that track and getting better at it, rather than blurring the lines between air bnb and -for example- booking.com.
Most of the hosts I know who use BDC have switched because they were unsatisfied in some way with air bnb. Certainly in the UK airbnb marketing is less visible than it used to be- no tv ads for a while. And there are gripes around compensation (which I would sort by placing a minimum and maximum claimable amount- putting in place a minimum claim would save a lot of hassle for the company and would be a clear message to hosts about needing to suck up a broken cup or a stained towel) and reviews, where they seem to be listening a bit more. So strategically I think they should consolidate their brand identity rather than diluting it with mergers and acquisitions.
A while back they bought a luxury brand. I grew up in that bit of the business. It is a nightmare and very hard to make money as the market for sublime luxury is relatively small and the standards necessary to compete make each and every property very costly to operate. Now I run 4 rooms in my house and 2 small flats at a relatively simple level and I make a better return than when I operated at the luxury end, and air bnb do OK out of me too.... and my guests are pretty happy with good clean rooms at a fair price.
Too much diversification could be confusing to customers and hosts, it may dilute the brand identity and ultimately generate less consistent returns together with much higher costs.