Fated SotFO is still the same raid, but with new mechanics added in Season 4 and increased loot.
Now, depending on the difficulty of the raid, the level of dropped items varies from 278 to 311 iLvl.
You can still get Tier Sets specific bonuses consisting of 5 inventory slots: Helm, Shoulders, Chest, Gloves and Legs.
Bonuses are activated when 2 or 4 set pieces are equipped.
Seasonal rewards for Fated Raids include:
new Feat of Strength achievements, Jigglesworth Sr. mount, the "Hero of Fate" title and Shadowlands Raid Teleports.
You can change it later in the top nav menu. Please note, that price of services might be different for different regions.
Also the currency matches certain region.