We're talking about private parties here, trying to grow their wealth for the future. What exactly are you proposing they do?

Government should embark on major public infrastructure projects and issue bonds tied to some collateral or benchmarks like for example a portion of property or sales tax in some area, for some limited period.

That's a great idea, let the private markets front the cash for infrastructure projects and let local gov bodies set the rate of return over a set period (using the tax fund). This means a small portion of tax money can go towards repayment and states/counties get their infrastructure upgraded faster. Can anyone weigh in on why this is a bad idea? I have no idea why this isn't already the case.

A lot of infrastructure is funded via bonds already, but the interest rate is fixed instead of tied to a percentage of property tax revenue.

This idea would have more uncertainty for the investors, so they'd want a higher return than for a fixed bond. Taxpayers would be less likely to vote for the measure because it would have to raise their taxes even more than a standard bond.

(that being said, bond measures often take the form of "a 0.2% property/sales tax is to be levied for the next 20 years to pay off the bond", which is actually pretty close to what is being proposed by the GP. The difference is who is left holding the bag if tax revenues don't meet projections)

Most of those bonds would be bought up by banks as usual, inflationary pressure would be caused by those bonds because of the temptation to print money to make up for the inevitable shortfall