fun fact but that is a real stretch to say she was the most famous TV actress in the world when she probably wasn't even the most famous on Family Ties
In 1986-87, when Family Ties was at its peak, it had a rating of 32.7, which means almost a third of all US households watched the show every week.
That probably amounted to 60m+ people tuning in, which is close to Super Bowl numbers ... every week. The TV audience was concentrated then in a way it isn't now. Yellowstone gets less than 12 million viewers per episode today.
Maybe you think Meredith Baxter was better known, but I'll bet more people were paying attention to the teenager than the hippie mom. But let's say she was no 2, or no 5. She was galaxies more famous than the most famous people on TV today. And she has a CS degree. Which taken together is more astonishing than Ben Affleck opining on LLMs.
I'll wager you at any point during Family Ties' run that more people knew who Baxter was, considering she had been a celebrity for 10 years going into that show. Also that's not how share works. A 32.7 share in 1986 is more like 29-30 million viewers.
If you're just going by ratings/buzz Lisa Bonet and Phylicia Rashad are contenders, but this is a weird definition of "famous" that is just "who's popular right now ignoring history and context". Like, Betty White exists.