If demons don't exist, then do angels exist ? If angels don't exist then does Satan exist ? If Satan doesnt exist then,,,, does God exist. If God doesn't exist, is there really any good or evil at all ?
When we pick and choose what the Bible says is true or false, we leave everything up to our own personal interpretation. That interpretation is guaranteed to be flawed. And while there are things in the Bible that people disagree about theologically, the disagreements result from seeking truth about what is contained in the scriptures and not dismissing what is in the scriptures completely.
Like I mentioned earlier, I'm assuming those saying there's no such things as demons likely don't believe the Bible and don't believe in God to begin with. And if that's the case, using the Bible as proof is pointless.
Now, if someone claimed to be a Christian and believe in the Biblical God/Jesus, but claimed there was no such thing as demons, then I'd have to question their beliefs to begin with
