That’s not always the case. Etemon, Digitamamon, and ExTyrannomon had evos in the DM20. They are considered the failure route.
DM20 is weird because the joke Perfects were the best thing in the original v-pet but some of them got miserably demoted in DM20 for some weird reason.
Yes! I exactly know what you mean. I still remember it clearly. After unlocking BlitzGreymon and Banchomamemon I started to focus exclusively on unlocking all the failure routes. I remember them being op in the original vpets, they were supposed to be a bit more challenging to unlock than other evolutions, and I wanted to use them in the Online D-1 Grand Prix.
Although I knew Monzeamon and Vademon where dead ends, I was still slightly disappointed they didn’t get evos. Still I loved that they included KingEtemon and Titamon, even though at the time I suspected the failure routes had gotten nerfed and their new evos where rather on the weaker side. Later on BladeSaber would confirm this with his findings.
In retrospect I do feel Puppetmon should of been replaced with Deathmon. Specially since what followed, the Vpet ver 20th, was the Pendulum ver 20th with Puppetmon. Poor Deathmon didn’t make it into an official japanese Virtual Pet (Cycle and Digivices not included) at the time.