Just have a mode for it

Would a new gamer even know what the yellow paint mean?

That argument is fundamentally dishonest. Nobody is arguing against visual cues. People are pointing out that at yellow paint at this point in time is immersion breaking. Guiding the player is difficult. However, some devs think that the problem has been solved. It has not. Yellow paint is a kludge, not a solution. Let's try to do better.

This problem has already been solved. The new Tomb Raider series does it best that I've seen. On the first 2 games it was tied to difficulty with the paint disappearing on the hardest mode and then in the last game they perfected it. They split the difficulty into, combat, puzzles, and parkour, so if you wanted you could have hardcore punishing combat, puzzles that basically solve themselves and parkour with a little help or any variation you can think of.