I am German and live in Geneva. I applied through the facilitated route in November 2021, when I lived in Geneva for 5.5 years and I was married to my Swiss wife for 4.5 years. Within a month of my application I got a letter from SEM with a CHF 900 bill. There was no confirmation that they have received the money but in April (5 months) I got an invitation with my wife to an online interview from OCPM (the Geneva cantonal authorities).
The interview lasted 45 min. It was in French but they asked me if it was OK with me as I have done the entire process in German to that point. I was OK. After a few questions about motivation, my CV (that I had to submit in advance) and my social and marital life there were 12 questions from a catalogue such as what is the Geneva flag, when was Switzerland founded, what are the largest Swiss Sporting Events, why was the red cross founded. They posed no problem.
After the interview the interviewer seemed happy and said he would send his report to SEM as soon as possible.
A month later (May - 6th month) my referees told me that they were contacted by SEM to comment on if my wife and I were giving the impression of a married couple in public. As some of my referees have known us as a couple for the 14 years we are together it was no problem for them to say (I had 5 referees, my boss, a colleague, an old family friend, a friend from university and a social friend).
In June (month 7) I was told that on basis of the cantonal report they require additional information and asked to send pictures, flight and hotel bookings to SEM that prove our married life. After sending 80 annotated picture that span 14 years as well as a plethora of hotel and flight bookings (I was a tad annoyed at that stage) I got a letter in July to sign again the confirmation that my wife and I have no intention to get separated (month 8).
In August (month 9 after applying) I was told that SEM accepted my application and in a month it will take legal effect. September I got the confirmation that neither canton or commune objected and in October I applied for my passport...
Hope this helps. Just keep going guys and girls... you will get there slowly but surely ..