We don't know how long wild eels live (again, the life cycle) but this is much shorter than a single lifetime of captive fish.
And these are just the headline threats for each stage, there’s myriad smaller ones. The reason for their decline is almost certainly a case of lots of small threats overcoming their ability to adapt, rather than one discrete cause.
There is an american Nematode parasite also that castrate the European eels.
Plus, overfishing, contamination, invasive species of fishes, drough, engineering of rivers, by-caught, propellers in dam pipes that cut them in chunks while swimming... And can't be breed in captivity.
The animal will go extinct in this century by greed, as usual.