[LightDestory]

Lets be fair, RDR2 is very graphic intensive, and not something that you'd be able to play on an old laptop/workstation in the first place..Considering that Its one of the latest games pushed out by Rockstar, Its requirements are not really that high, but ofcourse that can't be fully trusted until the game gets released fully and even then I am sure there would be mods that will allow the game to use lesser ram(like reducing textures)

If the game will be shipped with Denuvo... Also a mid-tier PC won't be able to run the game properly. 
Using mods is a little complicated because you will violate ToS of Rockstar because you will edit game assets without permissions. Any form of optimization MUST CAME from Rockstar itself.

The sad reality is that Game Optimization process and investments went worsen year after year, the need to sell the game and earn money doesn't allow a proper debugging and optimization process anymore.

Think about it: on older games it was already really hard to find bugs and low performance on day one and after months from game release, nowadays it is also common to get the "BIG PATCH" of the day one to fix the major problems.

On the first one to five month you are not playing the game, you are beta-testing the game for them.