Are these the reports you are talking about?:

https://www.hennepin.us/-/media/hennepinus/residents/public-safety/documents/Autopsy_2020-3700_Floyd.pdf?la=en&hash=1DD37B049B99FAE35949ADD1D04331BD45A86D01

https://content.govdelivery.com/attachments/MNHENNE/2020/06/01/file_attachments/1464238/2020-3700%20Floyd,%20George%20Perry%20Update%206.1.2020.pdf

I doubt he increased the pressure after floyd stopped struggling. All of his weight was on his planted right knee. The left, on the neck, was used for balance.

And this implies that there was pressure on his left knee, including after Floyd stopped struggling, and this furthermore seems very much different from what you wrote about before, including:

If the knee touching his neck was applying no downward force, there would be no reason/benefit to moving it.

The mnpls medical examiner report said that Fentanyl Floyd was complaining that he couldn't breath while he was still standing, before officer chauvin was even on the scene. These are not rumours. Read the report. Its publicly available online. Scroll down to the section about his advanced heart disease. Two main arteries blocked 90% and 75%. Also in the report. It also lists his fentanyl level as 11nl. Studies have shown that the average overdose victim has 9nl in their system.

There have been different reports, it would be good if you could confirm that I have linked to the same ones as you. The report I linked to describes this:

Cause of death: Cardiopulmonary arrest complicating law enforcement subdual, restraint, and neck compression

Manner of death: Homicide

It includes "neck compression" as a complicating factor in the cause of death.

From your previous comment:

It should also be noted that he never yelled "my neck hurts".

In the very beginning of the video I linked before, he did say "Please, the knee in my neck, I can't breathe shit.", around 0:20. Why would you write that? And Floyd did repeatedly say "I can't breath".

It also lists his fentanyl level as 11nl [sic: 11 ng/mL]. Studies have shown that the average overdose victim has 9nl in their system.

Do you have a source for those studies you mention? Apart from that, you do have a good point there, though the report seems to indicate that the lethal range for Fentanyl can vary very widely, at least from what I understand (page 16 and 17 of the above linked report):

It is reported that patients lost consciousness at mean plasma levels of fentanyl of 34 ng/mL when infused with 75 mcg/Kg over a 15 min period; peak plasma levels averaged 50 ng/mL.

[...]

Signs associated with fentanyl toxicity include severe respiratory depression, seizures, hypotension, coma and death. In fatalities from fentanyl, blood concentrations are variable and have been reported as low as 3 ng/mL.

In this randomly linked (and thus not necessarily credible) document, it gives examples of overdoses, and the two cases that had >= 11 ng/mL out of about 10 cases died: https://www.cdc.gov/mmwr/volumes/66/wr/pdfs/mm6604a4.pdf . This again supports that Fentanyl was at least a major part of it. I still don't understand why the medical report mentions levels as high as 34 ng/mL, but I have not looked into this extensively.

The neck compression cannot have helped, and he kept applying that minutes after Floyd stopped struggling (since else he couldn't have balanced, though you may or may not be right that the pressure was relatively light, I do hope you are right about that), instead of beginning to apply CPR (which I believe can help reg. Fentanyl overdoses if there is cardiac arrest) or similar or at least changing his pinning to pin only on the back instead of the neck, etc., etc., etc.