There's very little difference in the number of PCIe and M2 slots between Intel and AMD on their consumer platforms. The only difference really between AM5 and LGA 1700 motherboards is a lot more AMD boards have one M2 PCIe 5.0 slot, while only the very top Intel boards have this feature.
AMD has 24 PCIe 5.0 lanes directly from the CPU available for user, while Intel has 16 5.0 + 4 4.0. Cheaper motherboards might not expose all of those, or downgrade some to 4.0 to save on on-board components. In addition, both have more on the chipset, which is connected to (additional, reserved) PCIe 4.0 lanes. The best AMD chipsets have 12 4.0 and 8 3.0 lanes, while the best Intel ones have 20 4.0 and 8 3.0 lanes. An important point is that the connection between the chipset and CPU is twice as wide on intel (8x vs 4x).
So overall, AMD has more and faster IO available directly from the CPU, but less lanes from the chipset, and with a weaker connection to the chipset. If PCIe 5.0 drives become available and the transfer speed to storage is important, I'd say AMD is better, otherwise I'd say Intel has more IO.
Where "top" means "most expensive". The Z790 board I recently purchased for around $300 was pretty barebones and lackluster (no TB, meager IO from ports and headers, wattage constrained VRM relative to 13th gen TDP, etc), but it was the least costly way to work with an Intel proprietary technology.
It'll last another four or five years, but it was my first Intel build since the slocket days, and likely my last.
