Comparisons to Earth clothing and experienced heat load are somewhat instructive, but not entirely analogous. On Earth your experienced temperature depends on a lot of things. And the objective thermal solution is different: you have evaporative cooling, air flow, and limited radiative heat transfer between layers.
Thermal engineering for space is its own subspecialty of practice. The problem is usually rejecting unwanted heat. Therefore the passive elements of the solution are generally aimed at reducing absorption. A space suit contains something that generates heat: an astronaut producing 80-100 W of metabolic heat. Paradoxically the contents must remain within a narrow band of temperature in order to be safe and effective. In an Earth environment there are many ways to properly reject that heat. But inside a space suit, thermal regulation becomes difficult. Sweating is ineffective. Airflow management is problematic. Hence an active heat rejection system is employed, but as it relies upon consumables, it is limited in how long it can function. That said, central to the problem is not absorbing any more heat from the environment than is strictly necessary. Therefore space suits are highly reflective so that the only heat to manage is the internally-generated heat.
Spacecraft have similar problems. Their contents (electronics, etc.) generate heat that must be rejected, but luckily not quite as aggressively. The passive elements (outside coatings, etc.) minimize absorption. A limited amount of heat is kept around to create a shirtsleeves environment, otherwise you get the 0-10 °C of Apollo 13 just via the rejection from radiation. This is what we would expect from a typical non-blackbody object at Earth distance. The rest of the heat is radiated away via radiators on the service module. Keep in mind these are not car radiators, which are actually heat exchangers. These are pure radiative objects that are spaced so that at least one of them faces deep space and therefore has proper radiative efficiency. The space shuttle kept their radiators on the inside surface of the cargo bay doors. Water-glycol coolant circulates between the radiators and heat sources.
A notable exception is the black areas on the Apollo lunar module. These are areas that had to be kept warm for various reasons, such as needing to contain liquid water and liquid propellants at a comfortable temperature. The bulbous protrusions on either side of the ascent stage are the propellant tanks. The propellants for this engine need to stay at around room temperature. Hence they have black panels to provide some passive heat absorption. There are conductive and re-radiative paths from the outer skin to the tanks. Similarly there are black panels on the front of the cockpit. The LM lands facing away from the sun and the cabin cannot rely as heavily as the CM for heating from electronics, which are mounted on coldplates on the back. So the front panels absorb just enough re-reflected light from the lunar surface in front of the LM to keep parts of the cabin from getting too cold. The black panels on the descent stage are for similar temperature-control reasons. Sometimes you want a little bit of sunlight.
These days we make heavy use of computational radiative heat transfer (CRHT) to validate designs. The efficiency of a surface's ability to radiate heat depends on its temperature and on the amount of radiant heat falling on it. So something with as complex a shape as the Apollo lunar module will necessary have some facets facing others. Figuring out how to engineer the passive thermal properties of those surfaces is a simultaneous-solution problem with no closed form. As many of you can probably guess, we use finite-element models with adaptive refinement running on very fast computers to solve these problems. Grumman pioneered this technique when designing the lunar module: their finite-element model had a whopping 13 elements.
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