Can an ordinary person identify someone behind a completely separate social media account?

I've been wondering about this from a privacy and technical perspective.

Suppose someone creates a completely separate social media account using a unique email address that isn't connected to their known accounts, phone number, or public profiles. The AI accounts, a big example

In a situation like this, can an ordinary user realistically figure out who is behind the new account?

I'm not talking about obvious cases where the person reveals personal details, uses the same photos, usernames, or writing style. I'm more curious about the technical side. Can regular users see things like IP addresses or other information that could help them identify the person behind the account, or is that information generally unavailable to them?

If someone eventually identifies such an account, is it usually because of behavioral clues and mistakes made by the account owner, or are there other ways an average person can connect the account to a real identity?

I'm interested in how this works in practice across common social media and messaging platforms.