Yeah, but the Java 8 date/time API has been around for ~7-8 years, and is basically universally loved, while the original java.util.Date was hated for ages. Plus Java 8 date/time is based extremely strongly on joda-time, which hit 1.0 about a decade before that, and was also pretty universally loved.

So we're dealing with an API that has been considered great, and an excellent way to deal with dates/times, for nearly 2 decades. Seems like a safe bet to copy :)