For a boardgame, online matchmaking was already dead, it was released more than a decade ago, this isn’t something that you want to play with complete strangers at random.

I've been playing online with strangers for years. It's very easy to find a match and I regularly see over a hundred players in the lobby

If someone purchased the old one with DLC they can continue to play and access the DLC

I'd wager most people purchased the DLC for online play. There's typically more DLC maps in the lobby than the normal map

you can’t expect unlimited free updates

What's important is game preservation. It's now practically impossible for an average person who didn't purchase it to obtain a copy and play. It's been mentioned time and time again on WAN show - if a company chooses to shut down their servers then the technical information on how run a server should become open-sourced in an ideal world. Then the community can step in to run them if they so choose. This is especially true for multiplayer-first titles