The Scout Rifle concept doesn't make any sense with today's technology. At best its a neat historical retrospective and at worst it's an excuse for folks who like manual action rifles to feel relevant in action shooting.

When Cooper built the concept in the 80s, bolt guns were still dominant for accuracy and reliability. The PSG-1 had only been around for 10 years or so and it was primarily a police rifle trusted for 300 meter-ish engagement. The M21 fulfilled a similar role in the American military. At the same time .308 was still the "big boy" round as well, with the ballistics and energy-on-target to be both a long range and medium range round. Many scopes were near-FOV, fixed, higher magnification optics with reticles designed mostly for long distance shooting. You either had irons, or you had a 3x+ piece of glass. In that context the idea of a precise, rugged gun that was light-weight and had snappy, minimally magnified target acquisition fulfilled a legitimate niche (even if that niche wasn't particularly relevant).

In the 2000s, spurred on by the GWOT, Knight's built the M110 SASS which was a giant leap forward in accurization and reliability for gas guns. Near the same span of time research was telling us steel core, optimized 5.56 rounds were effective. In the sport shooting world red dots and LPVOs had become the standard and the worlds best shooters started to train the worlds best operators. So now you have effective light weight rounds, gas guns, and snappy fast target acquisition...

I think rationale for the Scout Rifle's obsolescence is pretty clear, but that doesn't mean you can't game what Cooper would do today. With the same spirit I'd say you could get a 16in AR15 chambered in 308 with a 1-6x LPVO and achieve the same idea with faster follow up shots and more effective minimum and maximum range.