I’ve seen alot of discussions about this, but I don’t think it’s that big of a deal. Say Way-com if you want. But the correct way, if I’m not misstaken, is wah-com: “Wah” is japaneese for harmony, and “Com” is short for computer.
If the pronunciation of Wacom is hard for non-asians, I think the pronunciation of Adobe is a bit hard for none-americans/english speaking people. We assume all e’s at the end of words are silent. I used to say “a-dob” before I heard Terry White pronounce it right.