From the paper: https://aclanthology.org/2020.emnlp-main.676.pdf
I'll jump in with a recommendation of how I would create the picture for my paper. Of course, reasonable people might disagree.
I write my papers in LaTeX, so I generally want a system that works well with the toolflow of LaTeX. Therefore, I recommend TikZ. It's a compilation process, where you write source code for the drawing you want and then after compilation you get to see the picture you created. Then, you get to debug why the picture isn't quite right, fix your source code and repeat.
It isn't for everyone. There is a steep learning curve. But, I find there is lots of satisfaction in being able to control every aspect of the drawing. I want my arrowheads to look like this, and I can get them to look like that, not the way that the Powerpoint developers thought arrowheads should look. Same argument for colors, paths, shapes, text, shadows, alignment (especially alignment) ... everything.
And, it's free and likely to be supported for the rest of my career. Not sure I can say the same for pictures drawn in other tools that I might want to use 40 years from now.
Also, there is an excellent StackExchange group (and plenty of others) that will give you quite particular help. It's a great community!
As for the picture you show, there doesn't appear to be anything special that would make it impossible to draw in TikZ. I wish I had a bit of free time to crank out the code for it and show you it is possible.
I have made quite a few figures and graphical abstracts for scientific papers and have two recommendations that are user friendly and do not involve a steep learning curve. The first is Adobe Illustrator, a vector graphics editor with intuitive but powerful tools. It can be purchased for a monthly fee and used on most desktop computers, laptops or iPad. The second is Procreate, a raster graphics editor app made exclusively for the iPad. The app can be acquired through a one-time purchase and is a great option for those with an iPad and Apple pencil.