Full mesh ofc chair is the best there is - even a cheap one.
They never go flat and last forever.
Once you go full mesh you'll never want anything else
My workplace office had chairs with mesh backrests, before they moved us all onto remote work contracts. When they did that, we had the option of taking one of them home with us to use.
I did not take them up on that offer, because I find mesh-back chairs (or at least the ones they had) to be intensely uncomfortable, leaving nasty indentations across the skin of my back. So I stick with padding because I find it actually comfortable. If it collapses, well, that's what the extra cushions are for.