I agree with that. I believe the plan was that he will be relatively alive for long enough to win an election and then step down later allowing Harris to actually fill the role. I understand the logic behind it, he’s the “safe” candidate, incumbent always has an advantage, and they correctly identified the issue of running woman of colour as a democratic candidate, American voters are, for some reason, aren’t as cool with that as they should be by now.
In the end I agree that they should’ve predicted his health problems earlier, but we know that on hindsight.