Actually that's not quiiiteeee right. Most drawing software doesn't require that much power unless you're using a lot of filters and layers and a really large resolution. Photoshop actually has an upper limit to how much ram it will use, Watch this video for more info about that.
The CPU/GPU doesnt really matter either unless you do a lot of video editing and/or gaming, or running a bunch of high-rez monitors, or plan on doing A LOT of multitasking. Heres a video about that.
the SSD/HDD thing is very much a preference thing, SDD's are faster than an HDD, but they have a much shorter lifespan, personally I prefer SSD's because I like not having to wait around for my artwork to save, and knowing my previous computer track record, my computer is more likely to fail because I spill something on it than the SDD dying from too much use. Here's a video about SDD's vs HDD's.
As far as windows VS mac's go, it's mostly preference, but you can probably get a PC with better guts than a mac for the same price. Also, most PC's have actual ports :V
Based on OP's other posts/profile it seems like they're trying to take steps to be more professional with their art, and the truth about that is that there isnt really a magic tool that will make your art more professional. You gotta experiment and find what works for you.