Its a nice game and you can definitely see where the future Arma games came from.
But is it worth buying today?
Not really.
The game is quite difficult, and while this is certainly fine as all Arma games are supposed to be difficult, the game features very limited checkpoints and only one save per mission, meaning deaths are extremely consequential and quite frankly tedious to deal with.
As a person who completed Arma 1 (Arma Gold Edition on Steam), I really thought I could go through this game.
I know this is a realistic military simulator and you should approach a product like this knowing what it is. As a game though, it isn't really that fun and the pain and suffering you have to deal with, trying to progress through the campaign is just not worth it.
It struggles to function on modern operating systems, and I could only get it working on an older computer, so for people seeking to buy this on modern hardware, I'd can't recommend it as it might not work properly.
The one save per mission is also a massive pain and a let down for gameplay and really break any flow the game has if you unfortunately die, and it doesn't seem like there are any fixes for this that I can find.
As I never played the game when it came out, the "nostalgic factor" doesn't hinder my outlook on a game like this. I can see where it has its merits but unfortunately it has far too many downsides that make it worth playing.
If you want a older Arma experience and something similar to the gameplay of Arma Cold war Assault or as its also known as Operation Flashpoint, I'd recommend Arma 1 (Arma Gold Edition) but even then that game is tedious and has its problems too, so perhaps stay away from that as well.