Horrible experience with Facebook recruiting

The recent experience I had with a Facebook recruiter for a TPM role, spanning over 3 months, is by far the worst I ever had. This experience stands out, as I have worked at and/or interviewed with other tech companies and all of them have displayed at least normal levels of professionalism. Below is a chronological order of events: - Applied for a position X through an internal referral and was contacted by the recruiter within a week for a different position Y (TPM role), which was to be honest a better fit. - The recruiter asks for phone screen availability for the following week. I provide the details the same evening. - No response from the recruiter for the entire next week. I follow up toward the end of the week, asking if the phone conversation is still on. - Recruiter says he didn't see my response and asks for availability for the week after, to which I provide my availability again. - On the day of the phone screen, recruiter asks if we can move our call by 1 hour to which I agree. Phone screen goes well and at the end of the call, recruiter asks for my availability for the week after the following week to schedule a call for the next step of talking to a team member. I respond with my availability for the requested week over email after the call. - No response from recruiter even at the beginning of the week when the call was supposed to be scheduled (10 days since phone screen) , and on following up, the call gets scheduled towards the end of that week. - Phone interview goes well and interviewer tells me an onsite would be scheduled and recruiter would get back to me with details. - On not hearing anything back from recruiter, I follow up with the recruiter 5 days later to see when the onsite would be scheduled. - The recruiter replies that details are being worked out and asks me for my availability for the following 2 weeks for coming onsite, which I provide by the next day. The recruiter says that I should be hearing the finalized onsite date by the end of that week. - I hear nothing back and at the beginning of the following week, the recruiter gets back over email saying there would be no onsite as somebody was identified for the role. - I respond back saying that it has been a very negative experience especially to hear about the onsite cancellation after being specifically told that one would be scheduled. I thank him nevertheless and ask him if he could refer me to a different role which I found to be of interest. - The recruiter offers to call and explain the situation, and agrees to refer me to the role I was interested in during the call. No confirmation of any referral after this. - 2 weeks later the recruiter reaches out again out of the blue, saying hiring needs have changed and if I was still interested in an onsite for the TPM role. - Recruiter asks for my availability, the onsite date is finalized, I was notified by the end of that week without any new hiccups and scheduled to be onsite at the end of the following week. - Onsite interviews were professional and were like what one would expect from a company like Facebook (however the interviews weren't easy, which I heard was a good sign, as I was told that if the interviews seem easy or pleasant, it was tending to a negative outcome). While seeing me off at the lobby after the onsite, the recruiter tells me that the team should have a decision by the beginning of the following week. - On not hearing back, I reach out to the recruiter mid-week, asking if the team had come to a decision from the onsite. - I receive the generic templated rejection email as a response from the recruiter. I thank him for getting back and ask him if there's any feedback that could be shared - what went well and which areas do I need to work on, for any potential future opportunities. No response to this till date. It is unfortunate that while the work culture at Facebook is touted to be among the best, the recruiting experience such as this leaves a very unprofessional and substandard impression.