Well, in my experience this is certainly not the case. I eat a lot of meat, also raw meat. I also regularly do short Water Fasts
of 3-4 days and my last meal is always eliminated the first day of the fast. So eating meat doesn't automatically give you a transit time of 2 or 3 days.
I'm certainly not saying that eating a lot of meat is a good idea for everybody. If you are a carb metabolic type/slow oxidizer, then you don't digest proteins very efficiently and the meat will stay in your body for too long a time. But on the opposite, if you're a protein metabolic type/fast oxidizer, then a vegetarian diet will be very hard on your digestive system.
I read in another post of yours that you have problems with high blood pressure. About 15 years ago, when I first came into contact with alternative health, I also tried to be a vegetarian and even a fruitarian. Being a protein metabolic type/fast oxidizer, this didn't work out well at all for me. It gave me high blood pressure and a constant "hyper" feeling. Now my diet is mainly meat with a lot of vegetables and my blood pressure is OK. I'm not saying that a meat based diet is ideal for everybody, but perhaps you should be willing to consider that a vegetarian diet is not ideal for everybody either.