@trs-80 Imo it's not as easy as comparing (or even just counting) some fancy pictures to really make a judge on the "most integrations" issue .
As a FHEM-user (without OpenHAB experience thouhg), I'd state there's at least three or four big systems missing (on the picture collection): HomeMatic / HomeMatic-IP, 1-Wire (it's more than DS18B20 ) and EnOcean. All of them are supported by FHEM, and additionally a lot of "special" stuff (like RS485 protocolls and many others). To get an impression, the commandref is a good starting point). Additionally, there exist a lot more "innofficial" modules for whatever purpose...
So in fact, I've seen quite a few people leaving FHEM in the past (it requires quite some familiarizon) and coming back to it, also from OpenHAB for it's flexibility. Also the level of comfort may vary from integration to integration.
So I'd state, there's not THE nor perfect answer to the question which controller supports the highes number of integrations
