> Everything in life involves hefty doses of luck. The alternative (i.e. without merit) seems obviously worse as it would be completely luck, no?

There is some level of luck / chance, but one can tilt the odds: more tutoring that allows for more practice to get better in the skill(s) that are 'merited', getting into schools with good alumni networks so one can 'luckily' bump into the right people with the resources you need.

Initially good luck can breed good luck in the second iteration/generation.

The meta-criticism (if you will) is that the initial batch of merited people can lock-in things for their (grand-)kids in future batches. There needs to be a way allow opportunities for future batches if their (grand-)parents from earlier batches were not 'merited' initially. Otherwise you basically get the ball rolling on an aristocracy.