Do you usually tell your players if you are using published material?
Sometimes?
My two PBP games on here were
Death in Freeport which mentions the module name in the title and my
Wildwood Red in Tooth and Claw game which mentions the setting and theme but not any of the modules I was running.
I usually pitch a game based on the theme or setting.
The last time I was asked to run a campaign I looked over stuff I had and came up with short elevator pitches of modules/APs I had with mostly trying for the themes of the modules with enough connection to the module title that I could remember what I was actually suggesting the next week when we got back together.
1 Rising Shadow in Middle Earth
2 Investigations in Pirate City
3 Completely Not-Haunted Funeral of Professor Jones
4 Starts off with Goblins
5 Plagues, Riots, More 2020 themes
6 Meteor Strike
7 Efreeti Aladdin
8 Ancient Dungeons
9 Baba Yaga and the White Witch
10 Punch Demons in the Face
11 The Mummy
12 Thundarr the Barbarian
13 Maquis in Devil-Nazi Land
14 Doctors Without Borders
15 Tatters of a Play
16 Masks Around the World
17 Dark Shadows
18 Spawn of Pulp Action
19 The Lothian Express
20 Chained Coffin in the Holler
None of these were things I was worried about my players having played before as none of them were into Paizo APs or Call of Cthulhu or 5e Middle Earth or Dungeon Crawl Classics.
Once they were interested in the Thundarr concept and then were all in on the crashed ancient Sci-Fi ship in D&D land premise at some point I sent them a link for the short free Iron Gods adventure path player's guide with some notes for how I was changing some things for my homebrew setting and then some more changes later to iterate on their character concepts.
Name recognition for new things you are interested in can be fine, I have signed up for a number of PBP games in part to try out an adventure path that sounded fun from Paizo's description or general buzz. It can be useful to be aware of if it would be something your players already know about from having played through it or run it or own and read it already. I have gone into a Temple of Elemental Evil game as a player even though I had already run the moathouse as a DM in the past, letting the group know I had done so but I would not mention or act on any spoilers. I have also played in a d20 Warcraft game where I played an ignorant barbarian troll because I did not have a background familiarity with the Warcraft setting like everyone else in the game. I also really like having the free short intro player guides for Paizo Adventure Paths as both a player and as a DM to refer players to.