Is there any benefit to putting a PCIe 4 SSD in a PCIe 3 slot?

Ssd sata and ssd nvme pcie slot compatibility m 2 gen 4 in gen 3 slot Kinda odd he spent nearly 4 minutes talking about the difference between Gen 3 and Gen 4 m2 expansion slot MSI PRO H610M-S DDR4 Motherboard, Micro-ATX

m2 sata vs nvme slot slot) In fact I've even successfully used a x4 adapter advertised as PCIe to run a Gen 4 drive at full speed in a PCIe slot: WD