Earlier quoted context omitted.
"legal" in a democracy is something that only a court can decide. I don't know what was Parler's size, but in any website with millions of visitors a handful will post aweful things each day. Were those 98 posts posted by the same user? Did anyone report them and Parler refused to take them down? Were they popular or downvoted with few views?
There is already a precedent from decades ago. The U.S. and pretty much every developed country on Earth have laws against distributing and possessing child pornography, because child pornography creates a market for exploiting children and selling the recordings online. The universal consensus is that this kind of expression needs to be restricted in the strictest possible terms, because it causes material harm to d…
Parler was not, and in all likelihood, cannot be convicted, because they were only sharing speech. The SCOTUS even ruled that anti-gay-marriage was considered free and protected speech because a good percent of the population has different opinion than the rest. Same for pro-Trump material. He had seventy two million votes just a couple of months ago. That's not the same as child abuse which is universally condemned by the entire population.