When did slots become commonplace? And NVME slots?

I have my new build with a 13700K i7 and an ASUS z790 motherboard which has 5 m2 slots When I first did the build, I only used 2,

2 slots — supporting both PCIe and — that allow you to expand your system with high-performance SSD storage Designed for the latest generation of NVMe

nvme 40 in 30 slot Supported CPU - Intel Core 2 Duo, Core Duo, Pentium D, Pentium 4, Celeron D Processors; Generation - Not Applicable; Memory Slot - 2; Memory Max

nvme in pcie slot Supported CPU - Intel Core 2 Duo, Core Duo, Pentium D, Pentium 4, Celeron D Processors; Generation - Not Applicable; Memory Slot - 2; Memory Max