Duo or oligopolies would be nice to have. We have monopolies, at the owner layer. That they own several buisnesses in the same sector, to placate monopoly regulations, does not reduce the lack of competition.

https://en.wikipedia.org/wiki/BlackRock

Im continously suprised that people, by assumption of brands and company names assume we still have duopolies or oligopolies.

You can own a whole industry sector without mergers and funny make pretend competition. The competition may hold true for software, because its such a young sector, but for everything else...