The vast majority of users that WP caters to are better served by Facebook Pages, Wix, Squarespace and Webflow.
Large and high traffic sites aren’t a great fit for WP either as the codebase was never meant for scalability and still maintains a painful developer expierence.
There are plenty of options, “JAMStack” included, that are still a much better fit.
Most sites I work on these days are either simple enough to be solved with no-code solutions, or complex enough that Wordpress is going to hold you back.
Granted, in most of the world, that's still a huge swath of businesses, but most of them realistically don't need a heavily customized online presence. Professional services are a great example of potentially higher revenue businesses that don't need a fully custom web presence. In competitive markets, I've seen plumbing firms/electricians/pest control all compete for SEO, thus spending more on web dev services, but they're the minority.
I work for a company that specializes in E-Commerce, with a narrower focus on high performance WooCommerce and custom Shopify development. We've seen some enterprise level customers start on WP and Woo for an MVP and then spend half a decade working to get off of it to their own in-house stack, or to transition to a more managed platform like Shopify. Each one has it's ups and downs, but by no means is any one a silver bullet. It largely depends on what your business requirements are and the expectations of your customers.
Selling a dozen individual SKUs with limited customization? Shopify is fantastic and has an extremely optimized checkout flow.
Need more customizations to the checkout or you want to create extremely customized user experiences for interactions like Add-to-cart? WP might be a better fit since you can control the entire stack. But WP doesn't scale as easily as Shopify (though it can scale, that's our job) so you'll pay a premium to develop the platform to handle that scale.
Outside E-commerce, I see a lot of potential for WP in the higher ed space still. Community colleges and trade schools especially as you can work towards a unified branding effort, while still providing customization and flexibility for teachers. I know a few colleges that keep a small staff of less than 5 people, who manage web development and maintenance for decent sized institutions.
All that I guess to say, is that WP still has a place, but that it's shrinking in scope, despite the increase in actual usage numbers. Only time will tell if the trend stays positive for another decade, or if we start to see a slip as other offerings continue to improve and mature.