The bottom line is: you need to plan to cover ALL your expenses. Taxes are an expense.
Whether it's a cheap one (possibly even zero or negative) or an expensive one depends on your situation, your investments, etc.
GCC had 5 years in a row where they had
a net negative $4 tax burden, besides many other benefits (such as tax loss harvesting and Roth IRA conversions).
I pay taxes each year, because we have a lot of real estate income. Real estate income is partially sheltered from depreciation, but if your properties cash flow a lot, which ours do, it's doesn't fully cover that income, and then you pay taxes on it.
It let us FIRE very early, so I don't begrudge the taxes paid now (versus if we had retired 8 years or so later on equities, we could also have no tax burden right now, but we'd have paid plenty of taxes along the way while employed for more years... I'll take our current situation).
So our income needs to cover our spending, and the taxes on that income, yes. (Ditto the side-gig income.)
What your situation looks like can vary. Try to optimize it, then don't worry about it.
Really, the first two sentences (the first one line) of my post covered it. :)