It’s only burning through the rows because you aren’t addicting for and writing an empty result when it shouldn’t calculate anything for that row.
Check it the following. You need to add an IF statement to write a blank on the array formula column if a primary column is also empty. If a row looks empty in the sheet, then Glide will not count it against your row limit.
Also it’s good practice to delete empty rows in the sheet. When Glide wires to a sheet with array formulas, the rows are still considered filled and adds a new row to the button if the sheet. This is why you delete the empty rows.
If set up properly, it’s much faster and more efficient than a script without affecting the row count in Glide.