The GOP-controlled Texas Legislature finds itself unable to pass a voting bill due to State Democrats refusing to participate in the meetings, leading the state to lack a quorum. The GOP has made several threats against the Democrats to take their seats, but why doesn't the GOP nuke the quorum and now only require a simple majority of members?
Why doesn't the Texas legislature nuke the quorum?
... why doesn't the GOP nuke the quorum and now only require a simple majority of members?
Any change to the quorum requires an amendment to the Constitution.
THE TEXAS CONSTITUTION
Sec. 10. QUORUM; ADJOURNMENTS FROM DAY TO DAY; COMPELLING ATTENDANCE. Two-thirds of each House shall constitute a quorum to do business, but a smaller number may adjourn from day to day, and compel the attendance of absent members, in such manner and under such penalties as each House may provide.
In addition to the answer by Rick Smith there is also the very big problem that the majority party doesn't need to work with the minority party at all.
If all you needed was a simple majority of members to conduct business what is stopping the majority party from starting sessions without informing the minority party? To me it sounds like they could just start a session when no one from the minority party is present and pass all the bills that they want to with no one to object.
While that may sound great for getting what they want pushed through they have to consider the fact that if they lose control the other party will just do the same to them. In order for them to not lose control in the future they can't do that in the present.
Even if Texas Republicans could change the quorum rules, they might not want to.
The Texas Senate Democrats chose to go to Washington, DC not only to deny the Republicans a quorum, but also to essentially lobby the US Senate Democrats to pass voting rights legislation to prevent the type of restrictions that the Texas Republicans are trying to pass. Passing this legislation through the US Senate will most likely require abolishing, modifying, or making an exception to the US Senate's filibuster rules. If the Texas Republicans were to change the rules of their legislative process to pass their bill, it might give additional weight to the argument that the US Senate Democrats should do the same.
I'm not 100% sure that this will be relevant, but it's worth noting that the U.S. Senate has a rule about quorum, and specifically is noted on the senate government website states the following (Bold for emphasis by myself):
Article I, section 5 of the Constitution requires that a quorum (51 senators) be present for the Senate to conduct business. Often, fewer than 51 senators are present on the floor, but the Senate presumes a quorum unless a roll call vote or quorum call suggests otherwise.
In particular, the issue with a lack of a quorum isn't always necessarily that big of a deal that nuking it is considered extreme.
Given the public departure of the Democrats from the legislature, it could be that they are unable to act as if they do have quorum ignoring that they don't, or that at least one Democrat is in the legislature suggesting that there is a lack of quorum.
It could be similar to a filibuster to an effect - to break a filibuster, you need the two-thirds majority to vote to end a filibuster...and if you don't have that, you're at the mercy of the person insisting that they still have the right to debate the law that is being filibustered.