If all 8 people know the mechanics, there's no need to type or use voice chat. The only reason you'd need to type is if you think one of your 8 is a moron who doesn't know how to do the mechanic and you're trying to warn them, at which point, you've already failed. There's no strict need for VOIP in this game; it's a help, but not a crutch or a win button.

The mistake I see many people here making is thinking this game is strictly affirmational like 95% of all the other games they've played in the past 10 years. It's undeniable that games have gone a little bit "soft"; rough edges are sanded down to be as smooth as a baby's bottom through tons of playtesting. Any time a player might spend an extra 30 seconds not knowing exactly where to go and what to do is a "problem spot" to be fixed. Like helicopter parents, games have become tools used solely to affirm that the player is really good and any feeling to the contrary is distressing to this worldview and they can't be allowed to feel that way. Sure, you may die in Call of Duty a few times, but you respawn 5 feet away without any consequence, ready to reassume your fabricated ubermensch persona, unassailable by the forces of the opposition.

It's fairly ironic that the OP has chosen Bloodborne as an example. Bloodborne, latest in the Demon's/Dark Souls milieu, which is part of a trend designed specifically to go AGAINST this affirmational coddling in video games (started with stuff like Super Meat Boy and Spelunky). Like Bloodborne, Coil doesn't bend over backward to provide the smooth experience that today's gamers "deserve". There's nothing impossible or unfair about the mechanics in Coil. You spent the time and the wipes in Coil either discovering or learning/perfecting the strategies used to clear each boss, just like in Dark Souls. You try different things, you discover weaknesses, you eventually succeed. That Coil isn't a loot piñata is not a valid criticism of its design. But alas, whenever a player is challenged in his worldview that he's not "good", they react: if someone kicks them for failing to learn mechanics in a timely matter or doing exceedingly poor DPS, they're elitist; if a fight is too difficult for this player to clear, it's a badly designed fight.