Ach, the usual stuff about NICs being re-re-re-created, incredibly annoying.

I thought the same - then I bought in September 2021 a "Lenovo Ideapad 5 Pro 16ACH6" which is when I found out that the "Realtek Semiconductor Co., Ltd. Device 8852"/"Realtek RTL8111E Ethernet LOM"/"Lenovo Device 4852" needs a brand new driver/module, respectively is not compatible with anything else.

I lost a lot of hair until I found "https://github.com/lwfinger/rtw89.git" (thaaanks a lot!!!) which made it work (reliable in my case, even with notebook "suspend-to-RAM").

As of kernel 5.14.5 (on Gentoo) embedded support for that NIC is not available, nor I think in 5.14.12 (not 100% sure - I did not install it, just peeked into it) :(((