1) it's often a balance between individual stats and team achievements to decide the winner I believe. Jorginho won the 2 most important trophies but he wasn't the most pivotal player in either team, especially not in Chelsea who has way more important players.
2) Winning Bundesliga is good, but Bayern wins every year literally. Copa del Rey is not amazing but winning the Copa America for Argentina in Brazil is.
3) The 8 goals from Bayern were in 2020 so it's not relevant. Messi scored both of Barcelona's goals against PSG, what else can he do if that team doesn't defend and had no one other than him producing in attack?
4) About the start of this season: the voting closed in October so I don't believe that it's a very important factor. Plus, unlike Lewandowski, he didn't do preseason and has travelled 3 times to south america in 3 months. His scoring+assist stats from January to July are huge.
5) Yes, the scoring stats of Lewandowski are crazy and far away from the rest this year but (something that everyone always forgets) Messi is NOT a striker, he's a playmaker. His scoring stats should be better compared to players like Bernardo Silva, Griezmann, Muller, Neymar, not to Lewandowski lol. Thing is, Messi has scored so many goals in his career that everyone forgets about this when comparing him to others and judges him with a completely different bar.