Features are deprecated and removed. It's uncommon but it happens when a new feature makes all use of the old feature unnecessary. Usually it's deprecated for a few versions and then removed some years later. You can always compile old code against an old standard.

C++ does have many ways to do anything. Most of that is historical, or due to features and library facilities with overlapping capabilities, or inherent to multi-paradigm programming languages.

Every C++ project is written in its own language. Its own "house flavor." This is true of all languages, but is particularly stark for a language as old, complicated, and powerful as C++.