RNG is here to stay, sorry to disappoint everyone.
There are 3 main ways that MMOs limit the accumulation of high end items/gear.
- Random Number Generator (RNG) - Drop/success %
- Incremental Accumulation - collect 1000 currency, trade in for item
- Hard Limits -24hr HNM pops, Lockout timers, Top 3 Provisioners, etc.
RNG is the most popular for developers, as it makes content repeatable, it adds an element of personal excitement to completing content, and it gives casual or first-time content uses a shot at obtaining an awesome item.
Incremental Accumulation is good for players as they see progress towards their item, but it usually has to be paired with lockout timers in order to prohibit spamming (which players will do, regardless of if they are having fun or not). The other problem with I.A. is that players quickly begin to tire of spamming content and the game stops being fun -- which means developers are having to work overtime to create new content to keep people from getting bored. Casuals also will lose interest in a game where they have no chance to get an item without dedicating huge blocks of time to boring farming. Spam-able content also encourages the use of bots.
Hard Limits are the least popular with players. They hate long lockout timers, they hate being the 4th provisioner, and they hate competing for HNM claims.
**There is also a 4th option - that is
Difficulty-based limits - [Making content exceedingly difficult] (Garuda, AV, etc)
This is almost never used as an exclusive limit, as it means much more work for devs due to having to track down and fix exploits. In a game as complex as an MMO, there will always be exploits and once they are discovered, players will rush in and dominate the content, making it useless in a week. This means that devs need to constantly monitor the content to make sure that it isn't exploited, which diverts from creating new content.
The devs use a balance of two or more of these aspects to put limits on endgame items like Relics, Darklight, or Multi-melded gear, and RNG is always part of it due to it is the least problematic overall.
Complaining about RNG goes with the territory, but I assure you that nobody would want to play a game without it.