While I agree with your sentiment which seems to be that fads...

While I agree with your sentiment which seems to be that fads and miracle cures come and go, resting on ones laurels is a fools game in the investing world.

Number of cycles you say - well a quote - "In initial lab tests, our battery demonstrated hundreds to thousands of cycles with 80 percent retention of its original capacity,”.
Of course, these are lab tests and may not represent real world performance. Or it could.

If these batteries outperform lithium batteries in every metric except number of cycles, then would that invalidate the tech from taking the lead? I mean we know "green" is the future, so if it doesn't require mining for minerals, is multiples cheaper to produce, has increased density, faster charging etc etc HOWEVER it occasionally needs some salt added or at worst fresh seawater replaced.... is this trade-off not worth it?

Having said that don't get me wrong, I recently invested here as I don't believe this tech is ready and have my doubts of it taking pole position... however... this is just one of many projects around the world trying to bring next gen tech - and reap the insane rewards a patent would bring.
One could argue it would be the most profitable invention ever to date and there's no shortage of motivation to make it reality - to simply sit back and say "nah it's not gonna happen" is ignorant.