"Not that type of game" in that PCs don't do (or are prevented from doing) any pre-scouting or info-gathering before wading in to a situation?
"Not that type of game" in that the players and GM are building the story together and are aware that being cinematic may take precedence over counting out the exact numbers.
One would hope, yes.
IME if they want that sort of info it's almost inevitable that they'll pick off and capture a straggler, then question it via persuasion or charm or bribe or pain or (if available) Speak With Dead. Higher-level groups would also throw Detect Lie if they have it. In a pirate setting they might follow one up to the tavern and make the capture when said pirate leaves said tavern in a less-coherent state.
Of course, that assumes that the PCs have those abilities, which is not a guarantee. Or that a living pirate will tell the truth (neither bribes nor torture are actually all that good at getting the truth out of people), and
speak with dead specifically points out how cryptic and easily misunderstood the replies will be.
And once it's established in the fiction via that questioning that the ship's crew number about 45 plus 8 others (captain, cook, bo'sun, etc.) it would be unfair of the DM to change that without a good, and potentially PC-learnable, in-fiction explanation. For example, the PCs might approach the ship and see 100 pirates on deck as they are entertaining an allied crew for the night; or they might approach and find nobody other than a skeleton watch as most of the pirates are away on a shore mission.
OK, let's assume that the party sees a skeleton crew on the ship... how do they know that what they see constitutes the
only pirates there? That there can't be a couple more hanging out below deck? Have they scanned the ship with X-ray vision? Sure, the PCs have talked to people, and they
think they know the correct number, but they can't be off by a few?
Daggerheart uses 4e-style minions? Any interest I might have had in the system pretty much just vanished.
I have no idea how it was done in 4e, but in Daggerheart, it's clearly stated that defeated doesn't
have to mean dead. All it means is that when the minion (or indeed, any adversary) is reduced to 0 HP, they're out of the fight--they
could be dead, but they could also be knocked unconscious, dying,
playing dead, running away, choosing to surrender, and so on. The player
can say that they're outright killing the minion, or the GM can simply assume that the PCs are killing them, but that doesn't have to be the case. They're not coming back as adversaries in
this scene (or possibly ever), and that's the important thing. But it also means they don't really have just one HP.
I try to think of how monsters and people would defend their homes, and the PCs sometimes suffer for this. Very first adventure in my current game, a 1st-level party wandering in the forest stumbled on to the lair of an Ogre. As said Ogre lived fairly close to the Caves of Chaos and was constantly being annoyed by the inhabitants there he'd rigged up a simple landslide trap as a defense, and when the PCs entered he set it off. Natural 20. 4 PCs instantly dead, the rest fleeing for their lives. Meanwhile the Ogre has a very nice lunch while re-setting his trap...
Right, and that's not "fair to the PCs" either (especially if you had done this in an edition where such a trap might bring the encounter above the party's level, and since that instakilled
four players, it definitely was), nor is there any way for the PCs to have foreseen such a thing--unless you want the players to be seriously paranoid all the time. Meaning that there's really no difference, in terms of "fairness", between this and bringing out some extra mooks to support the bad guy.
If they do some questioning (and get verifiably true answers) they don't need to read my notes.
If you're springing traps that can instantly kill multiple people in a party, then
I wouldn't trust your honesty...