I have had the Redmi Watch 4 for over a month and have had no restarts. I think it is actually fortunate for a reviewer to get one with issues incase this issue is common. I recommend reaching out to Xiaomi and looking into a warranty replacement and an explanation as to why you are having the restarts.
I have had my watch now for five days, and I have yet to see any of the software bugs described. Admittedly though I have not tried an emergency call.
However, I had to warranty replace my previous watch (a fitbit versa) twice to get a watch without random crashes and wrong tume displayed bugs. So I expect some common component to smart watches have issues that some manufacturers do a better job filtering in quality control than others.
I believe your Redmi Watch 4 on your region has software issues. Whereas I'm from Asia; specifically Malaysia. I have no issues of the watch restarting for no apparent reason. Nor I have any other issues. Also, I can assure you, you can attach a 22mm straps, you need to purchase a strap specifically for Redmi Watch 4 where I had online shopping: Shoppe Malaysia.
Very good informative review. I'd just like to say that I haven't experienced any of the negatives which you have stated, "so far during my week of usage and one large update". Greetings from Spain.
The Redmi Watch 4 is beautiful, has a bright, large AMOLED display and a great battery life. It is inexpensive and at the same time has a satellite connection and a brightness sensor, but unfortunately, it annoys with many software bugs. Our review clarifies where the light and shadows lie.