Let me guess, you have a website that won’t perform ajax calls the add media button has stopped working, or woo commerce won’t go one action further on any front, right?
Nevertheless, hang around WordPress long enough, and the probability of themes, plugins, and/or core WordPress updates conflicting with one another will happen. Most theme and plugins don’t encounter technical challenges when updating unlike core WordPress updates. However, WordPress websites often perform extremely well as long as themes, plugins, and core updates are well maintained on a consistent basis.
Long before there were auto enabled updates across all three platforms, I made a decent living — still do to some extent — logging into clients environments and updating necessary themes, plugins, and core updates.
I’ve had my share of WordPress core updates that have halted any and all web activity, including the administrative dashboard — the latest experience was the WordPress 5.X update (nightmare). WordPress 5.5, jQuery Migrate 1.X was a planned stage removal in regards to updating WordPress’ overall jQuery version — virtually broke ever plugin and theme known to man, including the very popular Classic WordPress Editor and Yoast plugins.