GA4: No Event Category, Action & Label

Compared to UA in GA4 there are fewer restrictions and required fields/parameters.

The most notable difference regarding events is 4 parameters that you could send together with every event to UA (excluding custom dimensions):
• Event Category (required)
• Event Action (required)
• Event Label (optional)
• Event Value (optional)

In GA4, the naming convention is much more flexible and it only depends on the person who is implementing the tracking setup.
In GA4, there is a parameter called Event Name, and then everything else can be edited and organised according to custom needs.
No additional parameters, can be an option.
Or we could send 4 additional parameters that better describe the context of the event.

For example, we need to track "Request demo" form on the website.
We could setup and send the following event:
• Event name: request_demo
• product_name: dsp
• company_size: 99-250
• company_industry: internet and telecom
• annual_revenue: 50-100M
The last 4 items in the list above are custom parameters that can be sent together with the event.

However, there are some limits regarding the number of custom parameters that can be sent with a single event.