This isn't really too much of a shock considering that leveraging Fox's library for streaming content is the main reason Disney bought the studio in the first place. Putting the original content on the service is certainly part of the equation, but building on it is standard Disney operating procedure, so we can expect this won't be the last Fox titles that we're going to see brought back on Disney+.
What's interesting here, at least potentially so, is the use of the word "reimagining" rather than remake. It's at least possible that we're not looking at direct remakes of these films, at least not of all of them. We could see new twists in the formula, or perhaps some of them could become series rather than films.
With some of these titles something other than a straight remake might make sense. It's only been two years since we got a Diary of a Wimpy Kid movie, though it was a straight-to-DVD affair . It's only been five years since the last attempt to breath life into the Night at the Museum franchise. Home Alone was the highest grossing domestic movie of the year (and number 2 globally) when it was released in 1990. It's certainly the biggest name of those revealed by Bob Iger. It made a superstar out of Macaulay Culkin when he was just a kid. Culkin made one sequel and a pair of additional sequels, including a Made-for-TV follow up in 2012, were subsequently released.
"Logan." Sir Patrick Stewart lost 21 pounds to play Charles Xavier as elderly and sick. Stewart claimed that he had a steady weight since he was a teenager and had never deliberately lost weight before.
Disney+ is looking to have a mass of both library and original content when it launches in November, and in the months and years that follow. It's going to make the service incredibly attractive to a lot of people, likely making the service a major player in the streaming game from the beginning.