I guess you don't consider Jordan, Woods, Gretzky, Montana, Ali, Shumacher, Federer, Navratilova the best either even though the reason they're considered the best is because of the many championships they've won
5 out of the 8 examples you have given are not involved in team sports, but individual sports, so in sports like tennis, golf, boxing, athletics etc. it is perfectly acceptable to judge who is better based on the number of championships/tournaments he/she has won over the years, or on the record of wins/losses between two individuals.
The same cannot be applied to team sports …. Would Podolski be as prolific if he was playing in the Polish national team as he is with the German national team ?? Having witnessed the Polish team at Euro2008 I would have to say no :o)
A striker relies on receiving good balls from midfield or good quality crosses and this was severely lacking from the Polish players.
Another example, take Alan Shearer, England’s centre forward for many years …. He played for Southampton, Blackburn Rovers and Newcastle …. and if I’m correct he only won one Premiership title in his whole career … no FA cups and no League Cups … yet he was considered the best forward in the country at that time :o) He represented England but did not win any trophies at International level.
When comparing strikers … one looks at the goals scored, goals per game ratio, appearances for their club/national team and not necessarily the number of trophies they have amassed :o)