Settle this for me. Does referral work?

Surest shot to get the guy to read your CV/ give you an interview. It's the ticket to the party, whether you get laid or not depends on your game.

Depends. At amazon referrals are of 2 kinds: one for people whom you know first hand. And second for people whom you don't know but feel they could be a good fit (for example people reaching out for a referral via LinkedIn)

I think the former option works better.
Pro tip: if someone you know works at a company, ask them to send your resume directly to the hiring manager if they can.

It can increase the chances of getting invited to an interview slightly, but not by much.

So how does it work? I have around 20 friends working at <10 companies. So I can get ~10 referrals.
But I am planning to apply to ~150companies so that 10invites me for interview and hopefully I crack 2 of them.
Now when I reach out to people on LinkedIn - takes 2-3 days to accept connection requests, then 2-3 days to reply to first message , the after several reminders I get the referral (whole timeline is 2 weeks for 1 referrals)

Any idea to improve this process. It is for this reason I just go to the website and apply myself. What are you guys doing?

Refferal from relevant person works most

Sadly it is one the most effective way of getting an offer. Really skews the market towards preachers and extroverts.

Got all of my last gigs through referrals