Is it okay to take two classes on my first semester?

I am joining OMSCS in spring 25, and I have been reading all sorts of warnings about how taking two courses is a taboo. I do realize underestimating how much work it takes to be successful may be very costly down the line, but how was your experience? To top it all off, how much worse would it be if I somehow joined the GA course as one of the courses in this semester( to try and knock it off early).

Background: CS bachelor's and a software dev for a couple of years. Nothing fancy

Edit:

Thank you, everyone, for taking the time to explain your personal experiences. I was hoping to get a good feel for how current students feel about it. And it is clear most of you agree with the official statement from the school. I will plan for one class for now.

Side note: if anyone has good suggestions for a first class in ML Specialization, I am all ears.

Thanks again!

Happy New Year, everyone!