Well for me my new video card has forced my pcie bus to go pcie 4 so my nvme drive has to now run in a daughter card. So my next nvme will be pcie 4. And i want a 2tb.
The concern may be that if devices of both classes are used in tandem, then all lanes may be forced to the slower speed class.
It's a legitimate concern and so dependent on details of all devices involved, including firmware and operating systems and driver revisions, that I'd share that concern from a planning perspective.
I can say that I have systems that do not behave this way, but nothing modern, and nothing that supports PCIe 4.0, while at the same time, there are plenty of reports of AMD boards / CPUs / etc. being finicky with PCIe 4.0. Including some annoying and arguably unnecessary workarounds needed to get certain configurations running.
I absolutely get wanting to avoid that situation where possible.
