Clearly they prefer their Vision Cones mini-game instead of the 5e system.
Rules of 5e just state: "You can't hide from a creature that can see you clearly." Creature seeing you clearly or not is usually determined by DM and requires his own judgement. The DM's role is reinforced by: "The DM decides when circumstances are appropriate for hiding." Thus, Vision Cones are not infringement upon 5e rules, they are an attempt to simulate DMs ruling. We might agree, that Larian's vision cones are too generous, but shouting "Follow 5e" is not a valid feedback or concern in this case.
