Maybe not for those cases, but a lot of apps aren't as demanding as those. So I don't think you can say in general that the web can't compete with desktop apps,

Maybe not for those cases, but a lot of apps aren't as demanding as those. So I don't think you can say in general that the web can't compete with desktop apps, maybe only just for specialist cases. The web is good enough that it didn't stop Facebook becoming a billion-dollar company. Mobile is a different matter, but think on desktop how many services are fine to work web only on desktop with no desktop app (especially if they have a mobile app).