Extremely unlikely. Not for another 20 years or so, worst case scenario, and by then they probably won’t care about now.

First off, there’s way too many people who criticize the government to arrest everyone, secondly it’s completely unnecessary. Complaining about the government doesn’t really do anything other than allowing people to vent their frustrations and feel more content. It’s the same way Trump obviously isn’t going to “end elections forever” like people say, virtually every country in the world has elections, regardless of how actually democratic they are, because they’re a nice little ritual that lets you feel free and in control. It would be like saying that Trump is going to knock down the Statue of Liberty - he doesn’t have to.

Now, there are reasons to establish more secure lines of communication, like if you’re involved in actual organizing or if you’re either helping people do illegal things or planning to help people do things that could potentially become illegal - for example, shipping Plan B or trans hormones to people in red states. Laws in some red states about “pushing transgenderism on minors” could theoretically be interpreted so broadly that if you post information or supportive messages on a public forum and a minor in a red state happens to see it, they could try to come after you for it - but that would probably be found unconstitutional.

Using secure lines of communication for routine, everyday stuff helps keep those lines secure by generating more chaff they’d have to sort through, as well as familiarizing yourself with it and getting more people on board. However, you shouldn’t scatter to the wind preemptively and self-censor, beyond just not fed-posting.