What is the basis for some contemporary scholars’ objection to the presence of lines on mosque carpets for the purpose of straightening the rows?

Question:
Honorable Shaykh, may Allah grant you success. He says: It is reported from the Rightly Guided Caliphs (may Allah be pleased with them) that they used to send men to straighten the rows. Does that not indicate the permissibility of drawing the lines on mosque carpets, which some contemporary scholars have objected to?

Answer:
This is an unnecessary burden. Yes, I object to it because it is an unnecessary burden. Also, the followers rely on them and do not take care of it themselves; they do not straighten the rows or align their shoulders and heels. What is required of the followers is that they strive in this matter. If there is no line, it does not accomplish anything at all. Yes. And also, perhaps if there were no line, a person would not care; he would just line up with this line. This is an innovation, and it is also an unnecessary burden. It indicates a lack of concern on the part of the followers, as if they must have a line drawn for them. Yes.