Infrastructure is ethernet everywhere you can. Gateways and the like can an will change with technology. I've been doing building automation for a long time and protocols have changed and will change again. Large scale automation moves much slower than home automation but what we were doing 15 years ago is different to what we do today.
If you go for open protocols (zigbee/thread/mqtt etc) and well supported platforms you'll be ok and have an upgrade path in the future.