system
A chat on subreddit /r/pcmasterrace
human
Dual GPUs still have their place in industrial applications and machine learning, but for gaming having 2 GPUs is useless as there is literally only 15 or so games that support SLI and most of those games are real old ones from back when SLI got popular. For the average gamer, take the money you’d spend on 2 GPUs and get one better gpu as it will perform better for gaming undoubtedly.
gpt
Just as an aside its important to note that for almost all production workloads you didn't use SLI at all. The cards were almost always used without SLI tech.   

That is still the case today obviously