Of course. There's a reason oil clubs find it difficult to win a CL even after spending billions.
Pedigree, culture and "know how" is something you can't buy for money. PSG and City can buy all the players in the world but getting over the line is only something you do with hard work and people who have been there before - be it managers, players, directors and so on and on.
Like it's not a coincidence Real won 13 CL/Europeans is it also not a coincidence the likes of Milan, Bayern, Liverpool and Barca all won it many times - culture. And of course you also need some luck along the way.
With that said, it will eventually pay of for City and PSG just like it did for Chelsea (fuck no

).
Might even happen this season.