You will be required to do an engine swap at 36. You will take out the sensible 4 cylinder engine and attempt to cram a straight 6 under the hood. The car will sit in pieces in your garage for years before you eventually sell it for parts when your spouse buys a storage system for their garden tools that will need to go in that space.
The American rotary was/is the RX8. RX7 was banned in the US because it had a left hand drive and emissions regulations. But you might still be able to find one or two floating around
The rotary is kinda cool but there's not many mechanics that can work on them. So the Miata is probably the smarter choice.
"Middle age" has never been about being exactly 50% of the way through the average life span. It's much less about "how much time you have left" and more about the point where you can't realistically think of yourself as young anymore. The effects of age become impossible to ignore, compounding, and increasingly obvious.
It's basically just your 40s-60s. Not the exact midpoint.
Think of it as being a middle aged woman/man - timer starts when you're considered a woman/man, so I probably at 18. Then, being "middle aged" actually falls in the 40s-50s.