Going back to your original question, how old is your track pump?
I had a basic
Halfords one which had given good service over many years.
But when I replaced it with a basic Giant one which was on offer from Edinburgh Bicycles, there was a marked difference in performance.
In t'other words, the Halfords pump had worn without actually failing.
As regards putting tubes into a tubeless tyre, that will be a messy job.
I would avoid doing it unless I really had to.
Unless you fully clean the inside of the tyre, some of the sealant will get onto the tube.
That doesn't matter - until you have to fix a puncture at the roadside.
No problem if you have a spare tube to put in.