All networks have their limits. You just reached yours because of the number of users and the type of content being accessed. Most web usage includes video which has significant bandwidth and response time requirements.
How often have you gone to schedule an appointment and been on "infinite hold" while they wait for their network to come back.
Or maybe you are a home with lots of busy users. Remember the COVID Days when everyone is home and trying to work and learn all at once.
Maybe your network started simple and ended up more like one of these.