Don't worry if you loved World. If you've got a Switch, then you can get Rise. If not, they'll probably make another MH game on the Series X and PS5 (and possibly PC) eventually, I mean, think in three different ways:
1) From a marketing view, they'll absolutely make another sort of "newcomers welcoming" for the next generation/group of people to get into gaming, which will likely be on the Series X, PS5 and PC. World was too successful for them to just get up and permanently leave the New World, and especially too successful for them to leave the entire property.
2) There are too many fans of World, and eventually Rise will also run through it's course just like World did. They'll eventually stop coming out with updates and then they'll announce something else and then that will be the next game that'll be hyped up.
3) There are just too many fans of Monster Hunter everywhere. After World got it popular with the West (yes, I am American, and yes, World was my first game) Rise will probably make the series even more popular. It seems that the only possible way that I can even imagine that they stop working on Monster Hunter games is either if an apocolypse happens or the entire staff of Capcom just suddenly disappears off the face of the Earth.