Being on ITV has probably helped the promotion in the UK
Plus the rosta has established names like The Hardy boys, Christian, Sting, Jeff Jerrett, Kenny Omega, The Young Bucks, Adam Cole and wrestlers people had never heard of such as MJF, Hangman Page, Darby Allin, Wardlow and Orange Cassidy
EDIT shout out to FTR too
Then there's the cross over with other promotions which sees wrestlers from NJPW making appearances which helps keep it fresh. But you cant but help think the rosta is far too big for the number of belts/tv time which is where the ROH titles have helped. People just get forgotten about like Lance Archer for example and Brian Cage (has he gone to IMPACT?)