Beginning with season 3 of Terrace House: Boys × Girls Next Door on April 12, 2013, Yamasato became a studio commentator on the reality TV series Terrace House. He has continued this role on each installment of the franchise, where he is known as the cynical one who enjoys highlighting the house members' flaws. In 2015, he was given his own spin-off on Netflix Japan's YouTube channel titled Yama Channel where he comments solo.
Yamasato co-authored two books that were both released on June 25, 2013. News no Yomikata Oshiemasu! explains recent political and economic words in an easy-to-understand manner, while Yamasato Ryōta no 'Tarinai' Eigo teaches simple English for communication.