I think this is an outdated take. Look around the league and see all of the top prospects being thrown into the fire early on. Especially when you are in the position the Nationals are in where the results on the field don't really matter. Garcia has two seasons of MLB ABs already and has not appeared completely overwhelmed, I see no reason to leave him down there much longer.
I am not saying call him up today and start him at SS, but if Escobar is still hitting in the .100s through April, just bring him up. Players can improve in the Majors, not just in the Minors.
Garcia isnt a top prospect.
Also,
Bobby Witt Jr: 125/.160/.292
Julio Rodriguez: .095/.174 /.143
Spencer Torkelson: 158/.333/.368
Plemty of top prospects are struggling early