Will external monitor damage my MacBook?

Short answer

What you’d like to do is totally safe. In fact, your MBP can handle more external displays than what you’re wanting to use.

Long answer

While I understand it, you shouldn’t let the experience of what happened to you in 2010 dictate what you do now. For example, a number of MBP models have had faulty GPUs and you may have been using one of those.

Regardless, to make a decision about your current setup, you need to use the specs of your current MBP to determine if it’s up to the task you need it for.

Your MBP actually has two GPUs, an integrated one (Intel HD 530) and a dedicated one (AMD Radeon Pro 455).

The important thing here is that the AMD Radeon Pro 455 has 2 GB of dedicated GDDR5 memory and is capable of supporting up to two 5K displays or four 4K displays. So, wanting to use it with one is not going to cause you any problems.

So, assuming the MBP itself is fine to run the software and/or hardware you need, then using it with an external display is not going to cause a problem.