Alpha build =/= Day one of Dragonflight. You’re correcting something incorrectly, what they said was accurate.
Alpha testing is done by an incredibly small number of the player base and is purely testing so any attempt to take anything in an Alpha build as gospel is pointless because almost everything in an Alpha build will change.
Soar is no longer nerfed because it is in line with the other dragonriding abilities. Even in the ‘slower than dragonriding’ state it was still by far the fastest way to travel in the old world short of teleports, assuming you had enough altitude to go as far as you needed and it could easily span a rather long range even before the update.