I certainly hope blocking people in the game does not stop you from matching into each other's lobbies and only prevents voice/chat with each other.
Xbox tried the "blocking people prevents matchmaking into their games" way in the early days of the Xbox 360 when accounts had a reputation system and all that. Know what the end result was? All the best players and pro players at games were waiting in 10+ hour queues to find a match. Because people were blocking everyone that beat them. So Xbox ditched that, and that was absolutely the correct call.
Blocking should absolutely never prevent matchmaking from doing its job and getting everyone into games. And listen, I hate Extraction Shooters. I played the Arc Raiders closed and open betas, and the server slam, so its not like I have no experience with the game. I lament that another fun PvE Coop Shooter was stolen from everyone to be added to the Scum Sponge genre. But I still think the game's matchmaking should function correctly.
These are the players that get angry when people say they don't want to play the game. And then act clueless when the game is dead due to low player counts. The people that also don't want to play in lobbies with other high level players and only want to Noob Stomp.
Its why I call this genre of game "Scum Sponge." Because it attracts all of the worst people on the planet due to the game design rewarding that kind of player behavior. I am thankful for it, because it means other games have less of them.