One thing that's become quite common here in the UK is multimode networks - bridging gateways for C4FM, D*, DMR and analogue into a single network 'room' - [CQ-UK](https://www.cq-uk.co.uk/) and [hubnet](https://hubnetwork.uk/) are examples.
These use software like SVXLink, [Allstar](https://www.allstarlink.org/) and [XLX Reflector](https://github.com/LX3JL/xlxd) with AMBE hardware at the server to handle transcoding between the proprietary networks.
It's all pretty cool!