Tbh this is first time I learned japanese being divided over mods. As stated on the written article, Capcom and Square Enix on Final Fantasy are those that "worried" by mods because they deem some stuff are too "over to the top".
On Assetto Corsa for example Japanese players embrace modding because it is one of the only way to fully experience driving over real course like The infamous Shuto Expressway network that back in the day used for street racing.
Seconding to emulation, for open world RPG you may find a lot of them on older consoles like pre-Gen 7 consoles (PS3/X360). To OP, assuming emlation is compliant with law on your country, older games are great too if you don't mind delving pre-2010s games.