As you can see, HTTPS is important to implement, but does require some diligence on your part to properly configure your site. As TLS, certificates, and HTTP advances, the barriers that previously held sites back from implementing HTTPS have been removed.
Progressive web applications require HTTPS because it is a higher level of user experience. They also require a registered service worker, which also requires HTTPS. HTTPS unlocks the modern web's capabilities; without it, your website is relegated to a smaller set of capabilities.
Because TLS ensures the conversation between the client and server is not altered by a man in the middle, and because eavesdropping is mitigated, all sites should adopt HTTPS. You are adding a level of trust for your customers, and opening the gates to the latest features the web has to offer.