No, I'm talking 390X vs 980TI. I've used the words comparable & similar, I'm by no means saying they're the same - of course there is a tradeoff for the substantially lower price.
As far as FPS in a lot of games, there's marginal differences (with the latest drivers for both of course) between the cards. Maybe 10% in the TI's favor in some instances at 1080p or 1440p, although that can increase to 25% in some situations. Beyond that (resolution-wise) the gap closes further, with the 390X even outperforming in some 2K scenarios and most 4K scenarios.
When it comes down to it, most HDDs are essentially the same. WD & Seagate specifically are actually produced in the same factories, the same production line. It's why their spec is exactly the same (depending the exact models, obviously). Both companies put out alternatives to their mainstream lines of WD Blue & Seagate Barracuda, but those two at least are essentially the same HDD. Happy to be proven wrong here, I'd be interested to see lifespan/failure rate stats to back up your claim WD have a longer lifespan - I suspect that's mostly bias there.
I agree, efficiency is not the only difference between some bronze & some gold units. There's definitely junk units in both bronze & gold 'ratings'. In the same thought though, there are quality units in both 'ratings' too. Consider I linked a quality made bronze unit, there's no justifiable reason to go for the 'gold' unit, unless the OP has a specific desire to have a gold rated unit. Both will perform as well as each other, with the B2 being slightly less efficient, but also substantially cheap (relative to the PSU cost of the build - obviously $35 is nothing really in a $2k build).