I assume this is more about amending the page of large size calculations than the page of lifting strength.
In fiction, there are many characters of Large Size. When it comes to tiering them their size alone can be an indicator of their statistics. This page explains which statistics can and can't be calculated from size alone. The physical attack potency, and with it the durability, can be estimated...
vsbattles.fandom.com
Draft change should turn from
Lifting Strength should not be calculated from size. While characters have to lift more bodyweight, lifting strength is the weight they can lift in addition to that. There is no way of telling how much more that is.
To
Lifting Strength could be calculated from size with clearly defined assumptions. While characters have to lift more bodyweight, lifting strength is the weight they can lift in addition to that. Given giant characters more times than not have to push around other giant characters at around their same sizes, it is only reasonable these characters can lift an extra weight equal to their own weight on top of their own weights.
Therefore, if the character demonstrates doing something like a push up (i.e. pushing much of its weight up with just its hands), wrestling with other monsters at around the same size, or flying by wings (or any non-supernatural means of lifting their weight into the air) then that should be an acceptable lifting strength feat.
If there are evidence the reference figures these giant characters scale up from can lift way more than their own weight (e.g. a centipede can lift up to 15 times its own weight), such consideration should be taken into account.
I am making this change during weekend if no one objects and no one applies such change.