By high end I assume that you mean something like some of the AMD Versal series, which are made on a TSMC 7 nm process, like the AMD Zen 2 CPUs from 6 years ago.

While TSMC 7 nm is much better than what most FPGAs use, it is still ancient in comparison with what the current CPUs and GPUs use.

Moreover, I have never seen such FPGAs sold for less than thousands of $, i.e. they are much more expensive than GPUs of similar throughput.

Perhaps they are heavily discounted for big companies, but those are also the companies which could afford to design an ASIC with better energy efficiency.

I always prefer to implement an FPGA solution over any alternatives, but unfortunately much too often the FPGAs with high enough performance have also high enough prices to make them unaffordable.

The FPGAs with the highest performance that are still reasonably priced are the AMD UltraScale+ families, made with a TSMC 14 nm process, which is still good in comparison with most FPGAs, but nevertheless it is a decade old manufacturing process.