The west is in decline because progressive values don't promote strength. They focus on class and are inherently divisive. Ironically, they only blossom in strong societies. The decline will allow other societies with a more conservative philosophy to take over and it will be their turn in a few centuries to succumb to the same tragedy. The baizuo tragedy.
You could just as easily say that the internet is the reason the west is in decline because it allows loud minorities, corporations, and bad actors to amplify their voices and promote their agendas, sow division and discord, spread misinformation, and more. Which is also overly simplistic and not the sole reason for decline.