This is how America got rid of large swaths of police corruption. Go back 100 years and bribing police was trivial, they made so little money that taking bribes was how they kept afloat financially.
Now days? An officer making $120k a year isn't going to take a $100 bribe to let a drunk driver go free.
In our current political system a politician has no accountability for accepting favors or campaign funds. There is no accountability for passing bad laws or being corrupt. This behavior will continue regardless of the base salary, or at least until there are repercussions against it. Currently there are none.
Hell, even today that's still the case in many countries with a large number of underpaid public servants - specifically China, where extorting bribes is considered a perk of the job.
Contrast to Singapore, which pays its members of parliament 3x the median household income and is tied for second place on the (lowest) Corruption Perception Index.
Also what does "make corruption illegal" even mean? Corruption takes many forms, and there will always be loopholes through which the most savvy can escape legal repercussions. I would much rather structure things so not being corrupt is just the easier, better, more natural choice. That's also not easy, but sounds more achievable to me.