I have no problem how people write God. I believe there is 1 God though given many names, hence I write always God.
Some write G-d out of respect, some write God out of respect
Some write god out of lack of respect, some write god because they see more than 1 God
And maybe some write god to irritate or trigger others or another emotional reason
God is linked with belief and belief is subjective, so anyone is free to write God however he wants IMO
You're leaving out people who capitalize or don't capitalize based on conventional English grammar. I would not presume the worse of people who are trying to be clear in their communication by following conventional rules of grammar.