Running Consistency vs. Speed
A repeatable easy run can do more for the habit than another test of fitness.
Plain answer
Speed matters when the goal calls for it. Consistency is what keeps you available to train. Most runs do not need to establish what you are capable of.
Fast feedback can distort training
Leaderboards and personal records are vivid, so runners may chase them too often. A system should also reward showing up.
Improvement needs recoverable work
Training only counts when you absorb it. Easy days, rest, sleep, and reduced weeks are part of the process.
Compete against an honest baseline
A handicap can make improvement meaningful without asking different runners to share the same pace.