They could literally just copy the uk platform. It’s clear, easy to use, accessible, centralised, non commercial, modern and the UK gov website design teams does a lot of their UI work in the open anyway.
It'd be interesting to see how much a multi-country effort to make a tool that collects tax information and applies a set of rules to the data to advise the user would be able to share. My impression is that it'd be a lot (the rules, of course, would be specific to the type of entity and local legislation).
As a Brazilian who has been using free government-provided tools to submit my taxes for decades (up to when I moved to Ireland, where I don't even need to do that), this is very interesting to me.
The very country specific tax logic part would by necessity be country specific built.
My point was more that there wasn't really a need to reinvent this wheel in terms of everything else. Not only is there a battle tested production system serving millions already, big chunks of it are in a MIT github repo.
That said I understand why the IRS doesn't just want to copy another country's. Not invented here and all that. But from the various countries systems I've used...the UK one is fantastic. Not just tax...same pretty clean UI and design across all the big gov sites.
I acknoledged as much already quite explicitly. Yes there are pieces that can't be copied.
>this would be like saying hey why not just use tailwind? that is like 10% of the equation.
No, my point is that they're going "I see there is a perfectly fine tailwinds implementation that would cover 10%"...but fuck that we're just going to reinvent the wheel on that 10% anyway.
Even you - by example - reach for an existing proven solution, tailwind. That's precisely my point...IRS did not reach for tailwind (UK's proven solution)...they decided that's too Not Invented Here...and built it from scratch.
https://design-system.service.gov.uk/