I have received many quotes for hair transplant number from different doctors.

My hair is thin everywhere, front, top, crown, and the sides of the hair. Each doctor I met with gave me a different number for transplants, but isn’t it of a concern with such much thinning all over my head.

Yes, what you are descriging is diffuse hair loss.  This is common as a genetic trait in some women and they may see it in their mothers, sistgers, aunts.  When this is the case, this is not a transplant situation, Diffuse unpatterned hair loss, typical for many women with genetic hair loss, should never be transplanted. I suspect that the doctors are looking at you as a source of paying off their mortgage. We would perform Scalp Micropigmentation on your scalp, which is a cosmetic unique stippled tattoo and will change the color of the scalp and make the thinning almost disappear.  This is not hair, but a highly specialized tattoo, see here for many good examples: https://scalpmicropigmentation.com/smp-for-women/