Is this game secretly dead? Just downloaded via Steam, can't connect.

Game servers are a bit wonky sometimes, just keep trying.

Also use the official Dreadnought Discord (the link is in the bottom right corner of the game launcher). There is a channel called 'PC-bug-discussion' or something along that lines where you can ping the devs (DN_Space_Ghost and DN_RayDog_Carrot) to notify them of the server crash. They are usually very quick to respond and restart the server if necessary.