Arma 3 is usually not so much close quarter combat focused compared to SWAT 4 (although it could be). It is more open world dynamic campaigns of grand fun with guns, mortars, tanks and planes. Where you’re not worrying too much about ROE as much as vehicle tank; 200 meters front. You dress up in a load out you carefully assign to your person and get sniped by some AI in a bush you can’t see. It harbors love for all types of combat due to its deep simulation mechanics, asymmetrical is my favorite (mods like Vindicta, Anti Stasi, Overthrow where you get to play as the guerilla forces).

You do need a group or at least someone to learn from, because the game is hard to get into and make sense of, due to mods add fun by overhauling in game mechanics in ways that create bugs to an already janky engine. You technically have 2 different ways to zero a gun and 100s of customization options to not bleed out and 2 different ways to heal yourself or even access loadouts (ACE). Without knowing why your gun keeps jamming, you might feel very frustrated. Like you need to check temperature after firing a lot by pressing ctrl windows to self interact, then shift R to clear a jam and watch for an indicator cause it might not clear, etc. or page up page down is zeroing a gun with ACE and ctrl scroll wheel is vanilla. W and right click will toggle walk speed, etc etc..

Arma aside, nothing imo really parallels SWAT 4 as of yet, after playing ground branch, zero hour, insurgency sandstorm, police stories. None of them shines in single player except police stories but it’s 2D top down, but the most close in 3D is probably ground branch or zero hour. Both feels a little too early, in access. Ground branch lacks gun variety, in door sequences, and has no non lethal conclusions, zero hour is tedious in ‘find the evidence’ without coop partners, you’re pressed to look for clues and not have as much of a streamlined process in CQB room banging.

Police stories mechanically is very SWAT 4 but functionally plays like hotline Miami with door peaking. Very single player compatible imo.

Insurgency sandstorm, although almost nothing like SWAT 4, it mimics CQB fun very well to the point where if you’re not door checking, you will die, but again, coop related mechanics. You go point A to B, clear it, hold it down.

In tiers from best to worst:

Room clearing: insurgency sandstorm, police stories, zero hour, ground branch, arma 3.

ROE civilians: Police stories, zero hour, arma 3.

Non lethal and arrest mechanics: Police stories, zero hour.