Apple SouthPark

In May of 2019 I bought a brand new iMac from Apple ***. I spoke with the employee who assured me this would have the ability to run Photoshop and Illustrator. My two biggest needs as a self employed artist. I only use this rig for business related stuff and have a 2011 iMac in my living room for personal. Almost immediately within a week of bringing it home I was experiencing lag issues. Spinning wheel of death, etc. Within two weeks it was crashing as well. This was the first time I brought it in to Apple I explained to them the problems I was experiencing and they said something along the lines of hard drive etc, so they did some restarting and reinstalled some things. This is extremely important to note: This is within a month of me owning this computer. At this point, upon bringing it in for the first time, they knew full well what I was using this computer for. I've been vocal I run illustrator and photoshop soley. Never once was it mentioned during this time it could be third party software related (Adobe) or this particular iMac model related (too slow). Extremely important to note. It was chalked up to something internal and they could fix it. Over the course of the next 8 months this continues. I bring it in, "they fix it" and it continues to happen. Again, never once was I told it was third party software related or iMac performance related. Finally, after constant trips to the mall, constant phone conversations, I'm done. I run a small business. The lag issues, the trips to the mall, the crashing, it's effecting my business and my mental sanity. This poor dude who has been insanely helpful since Day 1 can see the rage in my eyes. (Also side note, he was the guy who said I could get a refund if replacing the logic board didn't work, and it didn't work) He gets his store manager, an extremely unhelpful and condescending dude. He then proceeds to tell me in the most smug tone, "Ah! See there's the problem this computer is too slow for what you're tryin to do." Ran out of words.
Product_Or_Service: 2019 iMac 21.5 inch Retina 4k