Could RAID 4 be viable with a hybrid drive setup?

I'm just spitballing here...

RAID 4 is basically a bunch of drives running RAID 0 plus one drive containing all of the parity bits. The problem is that putting all of the parity bits on one drive creates a bottleneck. RAID-5 overcomes this bottleneck by distributing the parity across all of the disks. We all know the risks with RAID 5 these days when it comes to using it with the multi-TB HDDs, so I won't go into that. The alternatives are RAID-6, which is itself close to having unacceptable risk, and generally performs worse; RAID-10, which is expensive, and RAID-5 using SSDs, which even more expensive.

But what if you had a RAID-4 setup composed of HDDs for the storage portion, and an SSD to use as the parity drive?

Back-of-the-napkin math tells me that, at the right scale, this hybrid setup could cheaper per gb than arrays of RAID-10 HDDs or RAID-5 SSDs. So whether or not it's feasible rests on the assumption that making the parity drive an SSD would reduce the bottleneck sufficiently to bring the performance penalty and rebuild risks down to acceptable levels. If a single SSD wouldn't be enough performance, maybe a sub-array of 4 smaller SSDs in a RAID-10 configuration?

Is this wrong? If so, why? Does this already exist and I just don't know about it? How could I test this?

If this is a new thing, I propose calling it RAID 4H.