The Black Sea migration route is nowhere close to the Mediterranean routes. Like 200 incidents in the Black Sea vs 300k+ in the Mediterranean in 2022, with Italy, Greece and Spain being principal entry points.
Migrants routes may be used as a political justification but there have been a bunch of border incidents suggesting Romania does not in fact meet the criteria for Schengen.
[1] https://www.irishtimes.com/news/world/europe/main-cocaine-ro...
Disclaimer: I’m romanian.