The tasks view being a bit bloated by much information, it's important to minimise everything than can be. The following is a priority here.

in laptop and mobile view there is already a certain difference about how subtasks and checklists are displayed. Both have issues and should us a same minimalistic approach. No multi tabs on laptop, no horizontal scroll on mobile. Here is how it should look to be efficient :

Display all subtasks in a compact list, followed by a similar compact list of checklists. Use Statuses for ALL of them (as requested @ https://feedback.clickup.com/feature-requests/p/add-status-to-checklists).

Then, and only then, select a task or a checklist to open it.

This gives an instant and bright vue of everything important. No clicks, no scrolls, no opening/closing anything uselessly.

Life can be simple.