Yes, "think different" is important when looking to use a different piece of tech to accomplish tasks. Focusing on WHAT needs to get done rather than HOW to do it usually bears fruit. However, there are limitations to that which are directly related to the limitations of that target device.What matters is the output and the ease of achieving the same output.
You are still caught in comparing the interaction mode. If you want to do the same old thing on an iPad that you did on a laptop, then no it can't do.
But if you want to do a job, can an iPad better serve you in doing that? For many it can. For example teachers, sales men, students, doctors, sports coaches, etc have specific apps that help them do their job better, in a more mobile way. Doing spreadsheet on a laptop is more of a chore that these people want to avoid, than a requirement they love doing. If they used a laptop, they will be using a spreadsheet. On an iPad they have better apps to do that. What you are asking is, can they do spreadsheets on an iPad? First of all, if they must, they can. But the entire point is to find better ways to work.
No amount of "thinking different" can overcome the hard limitations of a particular device. "Workarounds" are just that... working around the deficiency, which by definition takes more time or resource to accomplish. Now whether the cost of those workarounds are outweighed by the benefits of the new device, that is highly subjective.