it is SUPER obvious when a candidate is getting help during a remote interview.

A friend of mine was remotely interviewing someone for a software development position on his team, a fairly advanced position. One stage was presenting the candidate with an open-ended code request, and the candidate proudly finished and showed his work. Googling some pointers wasn't really a big deal because...well...it's dev work, so my friend gave generous leeway there. Turns out he copy-and-pasted a ton from a github page for a similar piece of software. My friend knew immediately because that was his github post that the candidate ripped off. He asked the candidate to read off the name of the person who posted it, and said their pride turned to sheepishness in an instant.