Solar energy absorption is proportional to surface area, and radiative dissipation is also proportional to surface area.
By the way, Mercury is tidally locked, with a hot side facing the sun all the time. Even that hot side is not as hot as Venus.
There is no question, if you were to strip Venus' atmosphere away, it would cool down tremendously and probably be not much warmer than Earth, or even cooler depending on what albedo it ends up with.
This isn't even an open question or a mystery or an active area of study, by the way. This is very solidly known. I was hoping that by pointing out well-known but surprising facts like that Mercury is colder than Venus, and Earth absorbs more sunlight than Venus, it would encourage you to question your previous standpoint. But if you want to really challenge this point, then please at least do a little more to measure the strength of the limb you are standing on.
Atmospheric composition is not in general a function of mass, volume, and distance to a star, by the way. Due to feedback loops, planets can have multiple stable equilibria, and a history-dependent climate and atmosphere. That is why the concept of terraforming even makes sense. A planet with the size, mass, and location of Venus (or Earth...) can be made into a snowball or a fireball depending on albedo and greenhouse effects, and transitioned from one to the other.
How does volume come into play? Well because the higher the surface area to volume ratio of a spheroid body is, the more efficiently it interacts with its surroundings, in this case by radiation.
That said, you haven't said a thing to support the position that Venus's atmosphere is the causal factor, and not a consequence of solar inputs. There's no reason to believe we can learn anything about the Earth's atmosphere from Venus than there is we can from Mercury.
Look this isn't that hard. Venus has the atmosphere it does because it used to absorb far more sunlight than it does now which caused the increased albedo.
Solar energy absorption is proportional to surface area, and radiative dissipation is also proportional to surface area.
By the way, Mercury is tidally locked, with a hot side facing the sun all the time. Even that hot side is not as hot as Venus.
There is no question, if you were to strip Venus' atmosphere away, it would cool down tremendously and probably be not much warmer than Earth, or even cooler depending on what albedo it ends up with.
This isn't even an open question or a mystery or an active area of study, by the way. This is very solidly known. I was hoping that by pointing out well-known but surprising facts like that Mercury is colder than Venus, and Earth absorbs more sunlight than Venus, it would encourage you to question your previous standpoint. But if you want to really challenge this point, then please at least do a little more to measure the strength of the limb you are standing on.
Atmospheric composition is not in general a function of mass, volume, and distance to a star, by the way. Due to feedback loops, planets can have multiple stable equilibria, and a history-dependent climate and atmosphere. That is why the concept of terraforming even makes sense. A planet with the size, mass, and location of Venus (or Earth...) can be made into a snowball or a fireball depending on albedo and greenhouse effects, and transitioned from one to the other.