This is just a disagreement with the principle of free speech.

If you're only for free speech as long as it doesn't change people's minds, we have very different perspectives.

The issue isn't that people are trying to change people's minds. There are two issues here:

First, the rich have unimaginably more power in changing people's minds. This isn't sitting down at a bar and having a chat with hank to try to convince him to vote on prop 99. It is the wealthy putting their opinions on your phone, television, and billboards, reminding you of it multiple times per day. If politics is truly a contest of ideas, then the playing field needs to be level so that the ideas can be evaluated fairly, rather than it simply being a contest of who can buy enough ad space to brainwash people to vote against their interests.

Second, the wealthy don't have to change people's minds. They can purchase politicians by "donating" to them, going to million-dollar-per-plate dinners hosted by them, directly giving them money by staying in their hotels, etc. You don't have to convince a politician that they should vote on prop 99, you just need to pay them however much they want for their vote.

If the wealthy had exactly as much power in politics as a fireman or nurse, then I'd be all for their participation.