The lowest spec for cables requires 5 wires (CC, 2 * USB 2.0, GND, PWR) and a rating of 3A. CC pins are required for USB-C, if they're left out most devices won

The lowest spec for cables requires 5 wires (CC, 2 * USB 2.0, GND, PWR) and a rating of 3A. CC pins are required for USB-C, if they're left out most devices won't charge over it [1]. 3A is (in my opinion) a reasonable choice, since pre-USB-C devices took up to 2.1A and backwards compatibility is important. USB 2.0 data lanes aren't required for charging per-se, but the older charging protocols preceding USB-C did signalling of the allowed current over the USB 2.0 data lines (otherwise, only 100 mA is allowed). If you want to build a board, compatible with all USB-IF certified chargers and cables and all USB-PD power supplies, that only takes 5 V, the circuitry is two resistors. BOM is always important and stuff, but two resistors is as cheap as it gets. If you just throw it on a board and don't even bother to do a 2 minute google search, I'd take that as an indicator of the effort behind the rest of the board. If it's obvious that it's not a "real" usb-c connector, deviations are reasonable IMHO (for example, a high speed scope connector or a port labelled "debug" on measurement equipment), but for power it's a bad idea. Some products use a "USB-C" power supply putting out 12V all the time (frying other devices connected to it) or save on the 2 resistors, leading to a lot of user confusion when devices will only work with USB-A to USB-C cables. To the latter point: Doubt it. HDMI has tried to include Ethernet (with optional data wires), which luckily was a huge failure (almost no one implemented it). DisplayPort was trying to become USB-C before USB became USB-C. Ethernet now often doubles as a power supply. SD card slots could serve as an additional periphery slot in PDAs with SDIO. The only port common on a modern laptop that didn't (at least try) to include some completely other feature is probably the 3.5mm headphone socket (probably since there is no standard committee and even agreeing on how the 4 pin extension should work was a huge mess). [1] The CC line is needed to determine which device is a power sink & power source. Otherwise, users might connect two 5V power supplies together and create a short (between probably 5.2V & 4.8V)