Yes - you run one or more Tailscale subnet routers instead of your existing concentrators, then slowly migrate to running Tailscale directly from new deployments at your convenience.
Running a subnet router is a matter of installing the Tailscale package on a server and authorizing it to route traffic to certain subnets over Tailscale.
It's an entirely different set of teams who run anything "on a server". Besides the gap in teams or legacy demarcations of responsibility, their next disqualifier is having to think about maintaining a server. At best, the network team has just barely automated their switches & routers with Ansible. The VPN concentrators are treated as black box. And NetEng seem to prefer to stay within that box!
Maybe we're just not normal? (UK/EMEA, public company)
(I wrote the article.) You're not that unusual, we just haven’t had time to address that use case directly yet. I expect an ecosystem of MSPs may arise to offer physical boxes, or some such thing, since the tailscale client is open source. (Or you could buy a Synology with tailscale on it I suppose!)
Many companies just run tailscale in a VM to replace their physical VPN concentrator boxes.
Running a subnet router is a matter of installing the Tailscale package on a server and authorizing it to route traffic to certain subnets over Tailscale.