Barcelona and Liverpool's good chances are indeed based on their good results, but more likely on statistics. Bayern have one more failure than Barcelona at the moment, but they are rated worse. Real and City's good chances are based mainly on a long-term (pre-season) assessment of their strength - the clubs are currently doing much worse than expected and they are not leaders in their leagues, but it is assumed that in the long run they will be stronger than their bright (currently) competitors.
As for me, given the ongoing epidemic of injuries, I am no longer sure of anything.
His assessment is based on what is currently happening to Man City and Real Madrid, these two strong clubs are not in their best form, they are starting to have difficulty competing after the new format was implemented. I think Real Madrid are worse than Man City, the defeats to Lille and Milan make their chances of qualifying automatically very small. Madrid will also face Liverpool who have always performed well this season. Liverpool and Barcelona may have automatic qualification to the last 16, Munich and City still has hope, but Madrid will have to fight to qualify through the play-off, depending on the results of the remaining matches.
City is only 2 points away from the top 8, while Real is 3. The chances of getting into the playoffs directly are quite good, as there is still exactly half of the tournament ahead, and teams like Brest and Monaco will most likely not stay in the top 8.
Besides, not getting into the top 8 won't be a big problem, because if I understand correctly, pairs like Real - City won't be possible in the preliminary playoffs. Although, in fact, I haven't checked the draw mechanism that will be used for a long time.