Let's think this through a bit.
The constitution and related laws give states the authority to regulate certain activities. Some states, let's call them Blue States, feel that they are negatively impacted by other states, let's call them Red States. The Blue States have all sorts of evidence that their citizens were deprived of important things because of the Red State laws and enforcement of those laws. So the Blue States go to SCOTUS and get permission to change how the Red States do things.
That seems like a good idea?
This is a tangent that doesn't touch the curve. Texas is objecting to the states in question deviating from constitutional methods in order to institute changes to their electoral process, bypassing the associated legislatures with their standing being derived from the broad harm done to the Constitution and the Electroral College process
States suffer an Article III injury when another State violates federal law to affect the outcome of a presidential election. This injury is particularly acute in 2020, where a Senate majority often will hang on the Vice President’s tie-breaking vote because of the nearly equal—and, depending on the outcome of Georgia run-off elections in January, possibly equal— balance between political parties. Quite simply, it is vitally important to the States who becomes Vice President.
Our Country stands at an important crossroads. Either the Constitution matters and must be followed, even when some officials consider it inconvenient or out of date, or it is simply a piece of parchment on display at the National Archives. We ask the Court to choose the former.