I believe that iPad Pro with iPadOS has a very long way to becoming a Apple laptop replacement.
On the hardware side, it doesn’t have enough USB-C ports, there’s no way to get a minimum of 16 GB RAM if one does opt for the 1 TB model, and there’s no keyboard that comes with the out of the box experience. Also, iPad Pro would be an absolute pain to work with even if you had Apple’s keyboard accessory. Try working with it on your lap.
On the software side, I believe Apple understands that even if they swapped macOS with iPadOS on iPad Pro most people would opt for macOS on MacBook Air or Pro. Why? Again, it’s not very usable if one wants to work on their actual lap. iPad Pro shines when consuming media content, held with one or two hands, and/or stationary on a desk using Apple’s keyboard accessory possible as a secondary monitor.
On the price side, I’m currently reviewing the Apple M1 MacBook Air with 16 GB RAM and 1 TB storage that costs $1861.18 including all taxes. Now, iPad Pro 12.9 with 1 TB storage, Wi-Fi + Cellular, Apple Pencil, and Magic Keyboard for iPad Pro 12.9‑inch cost with taxes is $2713.47.
In summary, if I want a laptop from Apple, then I’m simply going to get a laptop. On the other hand, if I’m needing a carry device for mostly consuming media, sending e-mails, cataloging all my PDFs and EPubs, and very light on doing actual work, then I would definitely opt for an iPad Pro.