I bought the new 2019 ipad air last week. Loving it! It's the perfect model for me personally.
If they release a pro model with OLED/MicroLED as rumoured then I might upgrade and give mine to the mrs.
I just look at the form factor of my 2016 Pro (and Air) compared to the 2018 Pro and know that any upgrade I do has to be to the new style.