Actually, most people in the US shouldn't have to do any tax prep at all. The IRS already has all that information, after all. The only reason the average US worker has to do anything more than a check a "this is correct" box is because a significant number of politicians intentionally want taxes to be annoying and time-consuming in order to bias people against the idea of being taxed at all.

Cynically, I think they don't because even they don't understand all their rules. They couldn't write the software even if they wanted to.

But yeah, I'd love it if this was the kick in the pants that is needed to get people to see how ridiculous it is that taxpayers need to pay a third party just to submit their information to the IRS.

They obviously can write the software. We know this because they already written it.

We know this because when you e-file if your tax return is one of the ones for which they don't actually need any information you provide and you made a mistake they tell you right then what your mistake is and reject the filing.

And billion dollar tax prep companies want to have business

And just to quantify that. Slightly more than 10% of the workforce are self-employed. For that 10%, the IRS has almost none of the relevant information. So "most people" in this context means 90%. I think most of us (even those in the 10%, like I am) would agree that 90% does indeed mean "most".

that way they can use google analytics directly.

for example, accessing the the California DMV website not only uses google analytics, it will log you into google.