One of the tenets of a non CO2, no Excel planted tank is low maintenance.
So doing lots of water changes is certainly NOT part of the goal there.
Nor is overstocking with lots of fish etc.
Nor is having just a couple of plants and that's it.
Read the advice for the entire method, not just some of it.
I top off with tap water, not much else. Tanks do not have any BBA, in fact, I've added BBA infested Anubias plants...only to watch the BBA die off and have healthy perfectly clean plants a week or two later.
No excel, no water changes, nothing.
You will have higher rates of growth, less CO2 competition if you use Excel or CO2 gas enrichment. So you can keep more species and garden more.
But that means more labor, and water changes(more to clean up after the gardening mess you make).
Plant species in terms of labor make massive differences, Ludwigia Red pantanal vs say a tank full of Anubias? HUGE difference and management will be very very different also in CO2, Excel and non CO2/Carbon enriched tanks.
Density of the plants also, generally, always add as many plants will fit.