What does the launcher do with regard to the operation of the game that cannot be done within the actual game itself? Is it due to a technical limitation or simply there for the convenience of the players? Are there alternatives to such methods of starting the execution of games?
They do this and keep their top selling games exclusive to their platforms. Games like GTA have shown just how much money you can make off micro transactions. No company is going to just jump out of that market. They use their top games so they are more liley to get people to just have it installed. That way you install the launcher, put in your credit card, and you are only a click away from handing them some money.
There can be positive benefits though, auto updates, update news, community messaging or content.
But mostly so they can get the hardest part of selling done, a valid payment method input.
What about games without microtx, like BG3
I googled a screenshot of the launcher, so this could be from an older version. It looks like they have a link to buy merchandise, digital upgrades, advertising more games by the company that you have not bought yet. Also links to submit submit a but, let’s them hopefully have less QA personal. Community link to help the longevity of the game for longer term sales.