2020 macbook pro 3rd monitor

Yes. The 13" Intel MacBook Pro does not support 3 monitors. Its a hardware limitation due to the Graphics card. It simply cannot drive more than 2 screens.

The 2021 M1 Max 14" or 16" MacBook Pros do support 3 monitors.

Apple no longer sells any Intel MacBook Pros so if you must have an Intel Mac, it will have to be pre-owned or refurbished. The 2019 16" MacBook Pro is the last one to support up to 4 displays at 4K.

MacBook Pro (16-inch, 2019) - Technical Specifications

If you need Intel and multiple display support, then you will need to buy a PC rather than a Mac, and there's nothing wrong with that. Buy whatever meets your needs.

2020 M1 13" MacBook Pro, only 1 external display at a max of 6K is supported. Link-> MacBook Pro (13-inch, M1, 2020) - Technical Specifications

2020 Intel 13" MacBook Pro, only 2 external displays at a max of 4K, or 1 at 6K. Link-> MacBook Pro (13-inch, 2020, Four Thunderbolt 3 ports) - Technical Specifications

Neither of the 2020 MacBook Pros support 3 displays in any configuration.

<< I'll probably be looking at a different manufacturer when it comes to replacing this laptop early next year. >>

There are several models of Macs, including MacBook Pro models, that can support the number of displays you desire.

That is NOT a defect, you have simply not bought a capable-enough Mac for the performance and features you desire.

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Readers here are almost all other Users, not Apple employees. The threat to switch to another type of computer when your needs REQUIRE that will only be met with "great idea!"

You do not say exactly which model/year/chip your Mac is. Different models have different capabilities with respect to external displays. For example, the M1 Macs only support one external display.

what sorts of information are you putting up on these displays? rapidly-changing stuff such as Video Editing ? or slow-to-change information like stock quotes, spreadsheets, and program listings ?