No,it isn't.
But no open and local solution will be - but you pay for that in terms of long term usability, resilience and data.
It's a choice a mature customer needs to make. Be cloud and manufacturer reliant,invest the time to do it properly or pay someone to do it.
And KNX.org works for me(even tried it with a VPN to be sure) - and do you really think that a standard that is supported by the largest companies in the field(Siemens, ABB, Bosch, Schneider, etc.) and has multi-billion of installations in professional buildings alone per year is not for the long term?