I didn't say MonHun doesn't weakpoint system, I disagree with glowing weakpoints which applied for 99% monster in the series. The 1% is where I admit being wrong way below.
I see where you're coming from with Boss that has different visual colour/effect on their bodies to notify a weakspot to players. That doesn't really applied for MonHun.
Head, limbs and tail are usually the common weakspots for most monsters. Having these "glow up" or "shape changing" during powered up/rage phase and doing unique attack with those monster parts doesn't mean much, because people are probably hitting those spots in the first place most of the time anyway. Which in turns allow you to break monster parts. Espcially with World introduces damage numbers and colours for easier tell.
See how funny about Nergi, its tail and spikes are breakable yet it doesn't count as weakspot in the in game book guide. When the head is such a common weakspot, hitting it repeatedly is no such surprise if someone breaks horns. But the point of breaking parts is to guarantee drop or higher drop chance of a crafting material, not necessary weak points.
Uraagan and Radobahn
And the notable Barroth with it head and legs being "armored up" with mud. Breakable, but definitely not weak spots.
And a specific case, Rajang
His arms are breakable and not weak spots. In his rage mode, his arms may glowing red and considered to be kinda "armored up", which becomes the worst place to hit at.
At least Capcom isn't sadistic enough to make these cases applied to most monster of their games.
Even for the lazies not looking these in game guides, in early game, with a few monsters, you can easily tell that you aren't hitting the correct place because your weapon attack bounces off when it has yellow durability.
Here I admit being wrong, but...
Zorah Magdaros is one of the few giant monsters fight requires non-conventional MonHun fight like Shen Gaoren, Lao Shan Lung and Ahtal Ka, which requires you have to attack in a scripted sequence along with using stationary turret like weapons. Zorah is probably the worst one of them all.
Like here you go using cannons or ballista shooting at this Godzilla far away. Then use a flyer to go on the weakened Godzilla, its whole body becomes an environment area for you to go around, the only place you can hit is these magma cores (which is also highlighted on minimap) and some minerals for you to mine.
In this fight, there is no mechanical skill involve beside knowing doing the correct interaction the game tells you so. The whole fight is so scripted that you never be able to finish with much faster speed. Not only that, the monster armor set is also crap.
The only other monster I remember kinda have this go hitting this glowing rocks on them is
Ahtal Ka. But thats MonHun Generation, the title right before World. At least, that is only the small part of the whole fight, unlike the Zorah case.
