Despite enthusiastic and creative marketing by Apple, an iPad (whether an iPad Pro or not) really cannot replicate the flexibility of a desktop computer - such as a PC or Mac computer. iPad is, however, an excellent companion device that supplements the full desktop computer.
For many tasks, an iPad or iPad Pro can provide a very capable alternative to a traditional computer. However, there are some tasks (such as “restoring” - or in some cases upgrading) an iOS/iPadOS device requires that the device is connected to a PC or Mac.
Returning to specific limitations, iPad does not support “dual head” configurations. Neither does iPad support an extended desktop (to which you may be familiar when using multi-screen systems); iPad can only “mirror” its screen to an external monitor, preserving the format and aspect-ratio of the iPad screen - or for media Apps, direct video output to the connected single monitor. Printing from iPad is generally limited to AirPrint - and whilst usable, lacks the control and flexibility of desktop print solutions.
To conclude, whilst I would personally not be without an iPad Pro, I would not myself rely upon it as a sole computer. If nothing else, sooner or later, a situation will be encountered that requires connection of the iPad to a PC or Mac to resolve a problem.
