Currently, to give the salesperson access to the Leaderboard you would need to turn on the Marketwide Account Access or that salesperson needs to be a manager.

The ability to see all accounts in a market and the ability to see another salesperson's pipeline revenues and activities should be indepedent features.

Please enable the option to allow all Salesperson's (who are not managers) to see the Leaderboard for their market in Sales & Success Center.