[SmG Sabre]

Steam > Origin > Epic games

The only reason why Epic games is still a thing is because of Fornite. Once fornite dies/players getting bored of it - Epic games will be long forgotten.

Steam in my opinion is the best choice. It has almost everything (community hubs, forums, announcements, client updates, product updates, press releases, leveling your profile with badges, etc.) while Origin is still just a online store.

Also, PUBG is getting better updates each month and the game will overtake fornite. Slowly, but it will.
Thus Steam will rain supreme in years to come.