IMDB requires 25,000 votes for a film to qualify for the Top 250. This limits the list to films to those with the most extreme amount of global distribution. This only requires 100 votes although most have several thousand.
This list also doesn't feature any films released for the first time after 2004. Many films receive inflated scores in the years immediately following their releases due to hype.
Finally, the IMDB Top 250 is only for theatrically released, fiction, feature length films. This excludes "documentaries" and anything with a runtime of less than 45 minutes. I find it absurd and disparaging. However this list keeps this rule, partially because it was easier as many of the highest rated documentaries are recordings of staged events which also have inflated scores due to being almost only watched by fans of the performers.
This list still has popular sensibilities but is broader globally.