The OEMs will use ever trick possible and do something like open GMAIL to claim 10 hours, but given my typical use I average 5 to 6. I make music using a software called Maschine.
It's a massive step up over my old( still working just very heavy) Lenovo Legion 2020, which would last about 2 hours given the same usage.
This is all subjective at the end of the day. If none of your applications actually work since your on ARM Windows of course you'll have higher battery life.