Whatever Happened To Isogenies?

WARNING: the SIKE algorithm is only for research purposes, insecure

And, so, isogenies looked to be the next great thing in cybersecurity in replacing ECDH for key exchange, and for us to move towards a post quantum world. For key sizes, it all looked great:

Type      Public key size (B)   Secret key size (B)  Ciphertext size (B)
------------------------------------------------------------------------
Kyber512              800              1,632                  768
Kyber738            1,184              2,400                1,088
Kyber1024           1,568              3,168                1,568
LightSABER            672              1,568                  736
SABER                 992              2,304                1,088
FireSABER           1,312              3,040                1,472
McEliece348864    261,120              6,452                  128
McEliece460896    524,160             13,568                  188
McEliece6688128 1,044,992             13,892                  240
McEliece6960119 1,047,319             13,948                  226
McEliece8192128 1,357,824             14,120                  240
NTRUhps2048509        699                935                  699
NTRUhps2048677        930              1,234                  930
NTRUhps4096821      1,230              1,590                1,230

SIKEp434…