[NonContro]

According to Tim Sweeney, yes:

https://www.forbes.com/sites/mattperez/2020/01/14/epic-games...

"Exclusives have been critical in gaining momentum in the presence of a competitor that began 2019 with more than 90% market share"

[Wohlf]

How is he defining market share? I find that number hard to believe simply because Steam doesn't have some of the most popular PC games like Warcraft, Fortnite, and League of Legends.