Néanmoins, le blockchain semble (être) en passe de devenir l’une des technologies les plus puissantes et les plus adaptées.
This question extends to a similar expression "semble (être) sur le point de X" for instance, but I have seen or heard native speakers around me include "être" almost as often as they drop it.
Which makes me wonder which is more common in speech as well as in writing? I mean, when "sembler" is followed by a prepositional phrase "en/sur/etc ..."?