There was no out of pocket maximum, you were denied for pre existing health conditions, and a surprise bill could show up anytime.
Now, you can buy health insurance even if you know your anemic kid will need $1.5M of treatment in the year, and it will only cost you ~$10k to ~$15k per year.
To be clear, today’s health insurance premiums are not premiums either, they are taxes, due to the legal ban on underwriting health risks and caps on premium price ratios between various ages. For example, my kid is going to use up more healthcare than he will probably ever earn in his life, before he even turns 7. Your premiums are what is paying for that, aka wealth redistribution via “premiums”.