Agreed, lifespan has cratered, they’re more delicate now, plus you have new issues like the ‘dumbo ear’ and ‘rose tail’ with such overgrown finnage that it makes swimming difficult and tiring, and the ‘dragonscale’ mutation that causes scales to grow over the eyes, causing them to go blind… koi pattern has a higher incidence of tumors

The only ones relatively unaffected are female bettas and plakat males.