I know that this is hard for you, because you come to the Bible not believing what is says and needing to "find the real meaning" from your various outside sources.
The book to the Hebrews is ALL about the BETTER things coming for Israel.
- Better things (6:9, 11:40))
- Better hope (7:19)
- Better testament (7:22)
- Better covenant established on better promises (8:6)
- Better sacrifices (9:23)
- Better and an enduring substance (10:34)
- Better country (11:16)
- Better resurrection (11:35)
- Better city (13:14)
- Better priest (Chapters 5,6)
- Better blood (12:24)
They look forward to a CITY to COME.
Don't tell me, let me guess: it came in 70 AD?
I have no idea what "real meaning" you are now attempting to force upon Hebrews 3:17. But it was about ISRAEL in the wilderness.
I KNOW you don't know ANY of the chapters of Hebrews, except in your fantasy story version.