I got contacted by a Google recruiter. Do they just spam people or is this a good sign that I could get an interview/job? AnswerRequest

Google receives over 2 million (cold) applications every year. It would appear Google has no need to spam anybody. Why would a Google recruiter reach out to you if those 2 million applications were all they needed?

But I'll share my experience.

Disclaimer: My opinions expressed below are based purely on my experience
getting hired, not any insight that an actual Google recruiter might have.

I was contacted by two different Google recruiters via LinkedIn, and I wasn't looking for a job at the time. I had received many, many recruiter messages, but these are the first (and only) ones I've responded to on LinkedIn.

I had a phone call with each recruiter and they gave me more information about the positions. Both recruiters already had teams in mind for me that they thought would be a good fit for me, based on what they had been able to find out about me online (GitHub projects, etc.).

Both jobs required me to relocate, but I was unable to do so for at least 7 months. I was really interested in one of the jobs (sounded like my dream job), so I was pretty disappointed when both recruiters said they would follow up with me in a few months, because 7 months until I could relocate was a long time. I figured I probably wouldn't hear from them again (it's probably not every day Google calls you and you basically have to say no).

But, a few months later, both contacted me again and I decided to follow up with one of the positions. I had a phone interview, flew to Seattle for an onsite interview, got hired and they waited 3.5 months for me to relocate.

I'm not sure whether they were just fishing or if somebody referred me to Google or what.

I've received many recruiter messages that were clearly spam, where the recruiter obviously had no idea who I was or what my skill set was. My impression was that my Google recruiters had done at least a little bit of research.

If you want to work at Google (and based on my limited sample size of 1 and the 2 million applications Google receives every year) it's very possible that it's better if Google comes knocking on your door than the other way around.