Two Video Cards or One?

I am an avid gamer as well as a professional content creator. I do a lot of 1080p video editing work and I stream regularly. I also do 3D modelling and animation plus, large format illustration. I use Adobe for the majority of it. My current rig is 9 years old. I have a ASUS PRIME Z270-A with 2 AMD Radeon RX 5600 XT cards, max spec on mb RAM. With Win 10 EOL, I started doing research and building a new rig. I put this together:

https://www.microcenter.com/site/content/custom-pc-builder-amd.aspx?load=62f0be0a-8505-4ec8-983a-4354963aec58

But, the one aspect I could not resolve was "Two Video Cards or One?". Video Editor in me says, "Yes, we need that!". Gamer in me is always shouting, "More frame rate, less tearing!" Animator says, "Less render time is always good." But, research online is rather ambiguous. I read that Crossfire and SLI are either dead or not supported any longer. So, I ask y'all. What do you think? I have been building my own for a long time. I still remember when dual Pentium IIs was the bomb. Video Cards have advanced so much that is one enough? Thank you in advance for any advice.