Frankly, UA is old. It gives you the data most marketers want, but they really only want it because it's what UA gives them. Bounce rate, for example, is a crappy metric. (I promise I can cut a B2B site's bounce rate by 10% instantly by turning off ads running to landing pages.) But that's what UA puts front and center, so it's what folks focus on. GA4 will be different, but it's ultimately a ton more customizable than UA. Rather than looking at the same few metrics, you'll be able to uncover information that actually matters to your business.