Q: HOW MANY SIMULTANEOUS USERS CAN A SINGLE ACCESS POINT SUPPORT?
A: This varies by device model.
Some low-end units can only support 10 concurrent connections. Mid-range consumer units around 50. Prosumer models such as the Asus RT-AC5300 can have a bit more than 200. Once you move up to professional model - such as Cisco - they can at least in theory support a few thousand.