I think the “people are free to believe what they want to believe” is a mistake. This is the very statement that relativitises opinions and belief systems with facts and creates the illusion that they are all equal.
Look at the “facts don’t care about feelings” crowd that believe wholeheartedly that statements pandering to their feelings are facts and disregard any actual facts as fake news. I don’t think it’s because they decided one day to pick and choose what is a fact and what is not, but they actually can’t tell that there is a difference in opinions, beliefs and facts in the first place.
People need to accept that sometimes the truth is painful, that it contradicts what you want it to be, and worst of all - that you may have been wrong.
Edit: that said, I think people are free to believe whatever they want to believe when it comes to unprovable existential esoterica like personal values, afterlife, religion, whatever. As long they accept it is a personal belief and not an universal truth.
I haven’t looked at the Lemmy API, but generally speaking hard or not is subjective. Try it, get your hands dirty. Take a stab at testing how it works. Set some very basic targets. Split it up into tasks. If one task proves more complicated than expected, split it up into smaller tasks. If you get stuck, move to another task. You can always get back to those later. Things fall in place with experience.