"for I, the LORD your God, am a jealous God" - Exodus 20:5
Says it all, really. This whole character trait is that he's a jealous little asshole. He's like Dolores Umbridge.
I'm aware Christians may make counter-claims, but I've read the old testament, and all he does is to come off as an absolute asshole - you either worship me, or else!
I wasn't too surprised (but it made sense) that he (Elohim) originally came from the Canaanitic pantheon. How else can you be the only god, yet people shouldn't worship other gods? He's not, that's how.
Not that it really matters, but trying to learn about (Christian) God by reading the Old Testament is like trying to perform maintenance on your 2024 vehicle using a manual from the 2000 version of that car.. Like, yeah, that was relevant once, and there's some overlap, but the situation has evolved since then. It's called the Old Testament because it is based on something outdated (again, from a generically Christian perspective). The Old Covenant (which is what the Old Testament is testifying to) was between God and the Jews, and was based around compliance with the law. That's why the OT is so full of rules and punishments.
Then, Jesus arrives on the scene and changed the game. His birth, betrayal, and death, represent a new contract between God and humanity (not just the Jews) wherein mankind is saved by God's grace alone. In fact, God has done a 180 on the whole obedience to the law thing. Turns out, God loves sinners, and prostitutes, and tax collectors, and prodigal sons, and all sorts of ne'er-do-wells that the God of the Old Testament would have reviled. From the death of Jesus forward (and maybe retroactively too, I don't know dogma all that well), the only thing necessary for your salvation is God's grace, and that is given to all, as long as you accept God into your heart or something like that. Basically, God is Darth Vader, and he has altered the deal, pray he does not alter it further.
Of course, as with anything A) religious and B) 2000+ years old, there's a lot of disagreement on like every aspect of the above. But, I think I've got the gist of it correct from a generic, if Catholicism influenced, perspective. It's been a long time since I had to sit through a theology lecture.
With all that being said though, I imagine that the reason the OT has stuck around in Christianity is that it's characterization of God as vindictive and capricious and obsessed with toeing the line is a very useful tool for keeping the plebs compliant. They get to have their cake and eat it too, as it were. "God loves you unconditionally sweetie, remember that, but also if you have sex before marriage you are DAMNED to HELL for ETERNITY!"
And use his omnipotent power to hide from you while watching your life play out in exactly the way his omniscience let him know it would before he even created the earth or you.
Because believers will listen to Christianity's divinely inspired interpretation of the Bible that says that. Non-christians won't listen to that. Therefore anyone who believes the earth is older has rejected Christianity. He did it to help identify the non-believers because he's a petty bitch.
I always found it funny how they'll sometimes try to justify their claims scientifically to give it an air of legitimacy. If god created the stars close to one another and expanded them to fill the sky over a single day, the skies would be dark for billions of years. A YEC could easily say "oh well god put the light there to make the stars look like they've been in the sky for a long time" but very often they just don't have an answer because they didn't think of one. Unfortunately, there's almost that will stop them from doubling down on their beliefs and just becoming more prepared for the next person they talk to
The debate between Bill Nye and a creationist is so rage inducing. It's a terrible premise and the fact that Bill even agreed to it gave the creationist credit.