Ya sure. Don't count on it.

Pool their trades. Then the public would know what's going on.

… and that should extend to a period beyond their term to ensure they aren’t just using the “public service” job to plan a huge windfall once they leave.

Honestly, Id prefer a system where when you are sworn in as a upper level government official, your net worth, aside from your personal home and regular use property, is turned over to the US treasury. And then your life is paid for by the government during your service. After you leave service, you are repaid proportional to how the country has done during your tenure.

Money is no object.

For any Congressional investment outside mutual funds open to the public, tax any gains at 110% and no deduction for any losses.

That'll take the financial incentive out of elected officials playing the stock market using insider information.

you either get to trade stocks any way you want or get to be in Congress, period

What’s likely to happen if 3 or 4 congressmen announce they intend to buy or sell a particular stock?

by Senators & House members in Trump's first term, and it is probably even greater now. When Congress critters get inside information they act on it immediately, and most likely share that info with their largest campaign donors and friends who are oligarchs.

Take that female Senator from somewhere down south whose husband is the president of the New York Stock Exchange during covid.
She and a select group of Republican Senators got advance notice of Trump finally going to acknowledge just how bad it was.
That afternoon, the SEC reported that they were tracking 20 Million in trades by her that afternoon, and still counting. Getting out of certain stocks that were going to crater because of the announcement by Trump in the next day or two, and getting into stocks that were going to do incredibly well due to Trump's impending announcement.

After the SEC reported that, suddenly the whole issue disappeared from radar........LOL

And the number of times Trump would make an announcement, and they immediately sell their shares "short", then two days later he reverses himself and they then buy the shares back when those same stocks rebound to what it was originally..............

Hell, it is being reported that MTG came into office with 700K, and a few years later they place her net worth between 15 & 25 MILLION....

This will help get some of the scum out of our government.