Richard Thomas is the narrator/adult John Boy Walton. He played the young John Boy in the 1970's TV series.
Compared to the original film, The Homecoming: A Christmas Story (1971), in this version the Waltons are minus one kid; Ben Walton does not appear.
Olivia saying she is "feeling reckless" is likely a shout out to their dog Reckless in the original series. Who passed away in The Journal (1978).
Toward the end, there is a present day scene that shows Elizabeth and a granddaughter visiting the Walton family cemetery and shows John-Boy's grave with the birth year as 1916 and death year as 1992 at the age of 75 or 76. Earl Hamner Jr., the author on whom the character of John-Boy is based, was actually born in 1923 and died in 2016 at the age of 92.