HA 52 - Still confused about colour gamut

Hello All,
Even after listening to the episode, I’m still confused about which colour specifications are good.
I have a Dell U3818DW that I won at a charity auction, mostly because I wanted to try an Ultrawide.
The specs I understand: 21:9, 3840x1600, 300 nits,1000:1, 60Hz.

Colour gamut: 99% sRGB at Delta-E < 2 (average), 99% Rec. 709, 78.1% DCI-P3
Is this good? I just assumed it was as this is a Dell U-series monitor.