This is 100% correct. My 2018 iPad Pro is faster than my 2018 Mac Mini across pretty much every task I complete. It also has (IMO) the best drawing interface available on the market - and the market for art apps on the iPad is huge.
ArtRage is being left behind, and failing to support iPad with fully featured, modern software with a good UI is not going to help that. It's sad, but it's true.
I am simply not interested in using desktop/wacom solutions any more for drawing and painting when the experience is slower, worse to use and less convenient.
I saw ArtRage 6 was out and I was really hopeful that the iPad app would be feature-complete, and receive the upgrade it's so desperately needed all these years. Sadly, it seems that isn't the case.
Anyone saying that full, feature-complete ArtRage can't work on the iPad Pro simply doesn't know what they're talking about. I hope ArtRage sees the light - it remains my favourite ever software for simulating natural media, but it's vanishing into the pages of history on its current trajectory.