Hi Cburngo,
Sealy uses mostly synthetic Dunlop (called “smart latex”) in their mattresses. If you had one of the Embody series you would have been sleeping directly on this synthetic latex (with no breathable quilting) but if you had one of the “Springfree” models with a latex core, then you would have been sleeping on polyfoam layers not latex because they all have fairly thick layers of polyfoam above the latex. It’s a shame that they did this and there have been several members here who have had issues with these after a very few years and in some cases have taken the mattress apart and removed the polyfoam and replaced it with better latex and ended up with a better mattress than they purchased (at inflated prices) in the first place.
You can gain some insights into all the different factors that are involved in temperature regulation in post #2 here and post #29 here.
In the comfort layers (which deal primarily with pressure relief) this is correct but with the deeper support layers (which deals with support and alignment) then mattresses.net has options from soft to firm. The thinner the comfort layer the more of the “feel” of the layers below it will “come through”. Layer thickness can play just as important a role as layer softness in a mattress in terms of what is soft or firm. I would also keep in mind that the Brooklyn Bedding uses quilted polyfoam above the latex (which will make the comfort layer a little thicker and softer than the ILD alone would indicate) while mattresses.net uses just wool (which will slightly firm up the “feel” of the latex).
Every layer and component in a mattress will affect the “feel and performance” of every other layer to greater or lesser degrees.
Phoenix