On just about every observable measure ... including cruise ships[1], guitar is dying in popularity. You might get a few minor bumps of new interest because of recent artists like Taylor Swift but overall, guitar is way down.
I learned guitar and never imagined that the instrument would fade but that's exactly what has happened. Electronic music and laptops are this generation's instrument of choice.
I think there are 3 reasons why the guitar is "dying" as the instrument of choice:
1. The explosion in popularity of EDM in the mid 00's to early 10's, and the prevalence of EDM elements now dominating pop music rather than the notion of a backing band; most pop bands now feature a guitarist, but the guitar is secondary to synths and samples if it is heard at all.
2. The rise of hip-hop, mixtape culture online, and hip-hop focused rock music in the 90's and early 00's, shifted popular rock music and the cultural zeitgeist away from a focus on guitar-driven rock music. Once again samples and synths became the focus, even in punk music. This lead to a new focus: "indie" rock and the internet could make anyone with a laptop famous.
3. The general decline in rock music quality. I might be alone in this opinion, but popular rock music in the early 00's to today remains bland and the guitar equally so. This era also saw the rebirth of hardcore and more extreme forms of metal where the guitar remains the focus, and creativity abounds, but out of the public eye.
I learned guitar and never imagined that the instrument would fade but that's exactly what has happened. Electronic music and laptops are this generation's instrument of choice.
[1] https://www.forbes.com/sites/bobbyowsinski/2013/10/08/the-de...