My opinion is that the gen 7 or 9 Core i7 is powerful enough to use for your purposes. You will be more likely to be short on RAM with 16 GB than short on processing power. Memory is relatively cheap. With Docker and DB and a VM possibly running, I think extra memory would be good. That’s something you can always upgrade later if you find you need more.
If you are wanting to upgrade to W11, then stick with Gen 11 or 12 intel CPU, Gen 10 was the last intel CPU compatible with W11. W11 will run VirtualBox, as well or better, than W10. Go with 32G of ram, if you plan on running VirtualBox, the more ram, the better.
I understand the situations about the CPU according if Linux runs as either host and guest (through VB) … huge thanks to share that important difference, that was my main concern. Completely understood about the RAM. I hope the Asus for its new ZenBook models do not come with soldered RAM as came with my laptop .
Recent CPU offers certainly a better efficiency, but are not mandatory.
I am still working with an 11 years old Asus laptop with i7 cpu. System: double-boot Windows 10 and Ubuntu 22.04. Has been upgraded with a 2 TB SSD, 8 Go RAM, and functions quite well for intensive work including desktop publishing…
My home desktop (well tower) is a first gen Core i7 with 8GB RAM and a couple newer SATA SSDs. It has a now older NVidia card that won’t play new games well at all.
It does really well with my day to day web surfing and email on Windows 10. I also dual boot using Ubuntu 22.04 LTS.
But it won’t run Windows 11. Rather it probably would but Microsoft has crippled Windows 11 to require a certain base level of hardware, or you don’t get updates. I haven’t really looked into it much. Windows 10 is just fine with me, and I can also boot into Ubuntu and get mostly the same level of performance.
From 7th gen. to 8th gen. as I recall there was a higher jump in performance. The difference between for example i5 7th gen and i5 8th gen is about 20% in performance, while between 8th gen. to 9th gen. less than 10% (just like between 6th gen. to 7th gen).
So when upgrading budget friendly from an older generation I recommend targeting 8th gen, as I kind of feel, that there’s more value for the money. (Did not really calculate, just estimate for myself, and I’m quite happy having my computers running on 8th gen CPUs)