When (not if) cloud gaming truly takes off, and it will, we'll lose any and all control over our games. So long to modding, so long to messing with .ini files to get settings right, no decompiling games, no games preservation... The Netflix model approach, where we don't own anything, we're 100% reliant on them to provide us with the service, where servers can (and do) get shutdown at any moment after X amount of years of support.
A world where we don't own the games, just subscription services with extra fees for XP boosters.
The ultimate live service game that so many of the big companies love.
PS: Also means no more cheating by the standard methods.