Note NOT an LLC.

As discussed in the comments, totally forget an LLC.

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The blunt reality is you should be completely fine doing that.

(1) You are indeed a US cit., (2) You have a US address, (3) You file US taxes anyway, (4) Critically you are NOT reducing the taxes paid in any way to anyone.

You'd just be "adding a few more clicks on TaxAct .com" for the LLC hassle.

As you say, if you become the next Elon Musk†, hire a solicitor and forget about it.

Many companies (say, Facebook) are founded on utter scams and lies, and they just "sort it out later".

Note that the IRS is completely screwed w/ Corona anyway. (They are apparently currently just sending out "We'll answer you in 90 days" letters.)

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† That bloke is half-Canadian BTW for those who don't know!

You need to commit to doing things the right way from the start, or else strongly consider whether you are able to do them at all. If you go down the wrong path, there are some mistakes that no amount of legal or accounting help can fix. There is an expression in accounting, 'There is no such thing as retroactive tax planning', which means that once legal actions have taken place, you often can't reorder them in a more tax efficient way.

This means you will need to do more self-learning, and/or hire a professional. I will do my best here to convince you of that fact:

I had a client once, US citizen and Canadian resident, who came in new to us, with a problem to solve. He had a comfortable Canadian job, and a US consulting gig on the side. He decided to incorporate an LLC, so the income would pass-through to him personally, and he thought he could avoid 'complexities' by not filing corporate tax returns. He happily filed his taxes with a bargain basement accountant in the states doing his 1040, and a bargain basement accountant in Canada doing his T1, and he even tried to properly offset his Canadian and US taxes against eachother with Foreign taxes. This means he reported his worldwide income on his US tax return [as a citizen], and his worldwide income on his Canadian tax return [as a resident]. Canada had the first right to tax his Canadian job, and the US had the first right to tax his US consulting income, and they each had the right to tax any 'overflow' on the other piece of income, limited by foreign tax credits. Of course he wanted to invest in his consulting business so he never even moved the cash from his US bank account operated by the LLC.

Ooops! His LLC income in the US wasn't actually personal income in Canada yet - because he never declared his dividends! And 2 years after he started doing this, he decided to liquidate his LLC, and sent his US funds to his Canadian personal bank account - which Canada considered the receipt of a dividend, for the first time! So the CRA happily lopped 45% off the top of that payment [because he already earned a healthy income in Canada], and even when disputing that, he was unable to actually claim the past years' taxes on the income, because the LLC accrual of personal income in the US isn't considered income in Canada, so as far as the CRA is concerned, the US taxes he had already paid were irrelevant.

He ended up paying a total of 75% in taxes on the income earned on that LLC, because no one he hired was competent enough to simply tell him to not register a passthrough entity in the US! [Even if he had declared the dividends each year, Canada might have considered that passive income and the US 'general' income, meaning there may have been a dispute over applicability of foreign tax credits, but I think in that case he could have been fine].

Do this the right way now, or face real consequences in the future.