He’s certainly up there with any elite young goaltending property there is out there. This isn’t 5 game sample of a 30 year-old backup. Dostal has been one of the best goalie prospects in the league for a while, was very good last year as a rookie for the Ducks and he was stellar in winning the World Championships with Czechia in the summer.
Comparing him to Lyon or Lankinen because “5-games” is a complete over-simplification. His start is a just a continuation of really promising development.