Sometimes, when movie-stars live a very long life, an entire generation is unaware of their film achievements.
In Poitier's case, almost two generation may just be vaguely aware of his accomplishments in movies.
In his early-50's, Sidney Poitier decided to take a break from movies, and did just two over a 14-year-period.
Then in his mid-60's to mid-70's Poitier became active again, with ten acting credits in the 1990s. Some good stuff but much of it was in supporting roles. The Jackal with Bruce Willis and Richard Gere was excellent; and Sneakers staring Robert Redford was very entertaining IMO.
Poitier, along with Steve McQueen, dominated the 1960s. Just my opinion.
Raisin in the Sun, Pressure Point, A Patch of Blue and to Sir With Love were diverse but all excellent movies.
Guess Who's Coming To Dinner was ground-breaking for its time, and most notable for being Spencer Tracy's final film. Tracy is my all-time-favorite actor. Certainly subjective but there are dozens of stories about award-winning-actors and actresses that would sneak onto sound-stages just to watch Tracy work.
In the Heat of the Night is my favorite Poitier film, where he starred-opposite the equally-brilliant Rod Steiger.
Of course, all the above are just one man's opinions.
However, if you ever get to see the low-budget-film, with a simple-story, that was shot in a mere 14 days titled Lilies of the Field ... and you are Not truly moved ... then feel comfortable that as long as you change your batteries, you will be around for a long time because you are Not human. And that's Not an Opinion!
Thank you Sidney Poitier.