You might be right, but I don’t think it’s as clear cut as all that. Allowing OW2 newcomers to grind out OW1 skins through playing the game is a way of keeping the OW2 newcomers around. OW2 newcomers who stick around are people who will potentially decide to buy a battlepass or a paid-for cosmetic.
I wouldn’t be surprised at all if the free tier of the battle pass (or equivalent) is mostly made up of OW1 creds to buy OW1 cosmetics with.