When consuming APIs you often want JSON in successful scenario. Which means, if you also have JSON in unsuccessful scenario it's a bit more uniform, because you don't have to deal with JSON in one case and plaintext response in other. Also, it sometimes can be useful to have additional details there like server's stacktrace or some identifiers that help troubleshoot complex issues.
Because it protects you from ISP or targeted MITM. Lets say your ISP decides to spy on users or someone cuts into the internet wire going from your appartment to ISP, without VPN they can fully see and modify all http traffic as it's totally unencrypted, in https traffic they can't see the content but they see domain names of sites you are visiting and exact time when you are visiting them. With VPN 100% of your traffic is encrypted and in similar situation absolutely nothing is visible or modifiable. Someone can MITM on VPN provider itself, but it's not really suitable for targeted scenarios, because those wires are in other part of the world than you, those wires are much better physically protected and even if malicious actors succeed they will have very hard time filtering traffic from different users from each other.
I also use Proton VPN. Most issues were with DE servers I tried, multiple DE servers (like DE#526) didn't work for me, but some others seem to be working. I also tried some other countries and they were working.
Sorry for a bit of off-topic, but for a note taking app I suggest checking out Amplenote (there is a free plan for browser and mobile apps). I discovered it recently and it's quite a life changer for me. Proper tag system for notes is a killer feature.
I always considered "MMO" as a synonym for "multiplayer". Anyway, if you take the word "massively" into account, you could also treat is as "massive number of players you could POTENTIALLY reach by joining one of the rooms" (word "potentially" as opposed to "actually reaching at any given moment"). In actual MMORPGs it's not like you can actually interact with all the people online at the same time, you still are limited by geometry and game logic of the world at least, like no one will ever gather in a single town because people are doing other stuff, or are from enemy factions, etc. And in many MMORPGs there is instancing going on, so even players in mob farming locations can be assigned to different instances and not see each other because of reasons.
Well, something like this is actually quite popular in modular synthesizers community. They have one type of modules called "Clock generators" which generate gate/trigger signals for given BPM (Like 1/4 or 1/8 or 1/16 rhythmic pulses for 120 BPM for example) and another type of modules called "Bernoulli gates", which basically allow to specify probability of input signal going to the output. Those beat-skipping metronomes with configured probabilities are then used to trigger notes or samples or whatever. Also, this is modular where you can modulate almost everything, including BPM itself, but that's a different story... Stochastic music approaches like this are often called "alleatoric music".
By MMO you mean MMORPG specifically? Because MMO in general is the most popular type of games imo... League of Legends, Dota, Fortnite, Valorant, Overwatch - all are super popular. Regarding MMORPG, I see a lot of youngsters play Genshin. I've personally been playing a classless WoW pserver lately.
When consuming APIs you often want JSON in successful scenario. Which means, if you also have JSON in unsuccessful scenario it's a bit more uniform, because you don't have to deal with JSON in one case and plaintext response in other. Also, it sometimes can be useful to have additional details there like server's stacktrace or some identifiers that help troubleshoot complex issues.