The discussion is actually getting bitcoin without actually using fiat as others do not think something like that is possible and I say that such thing is possible but it’s not rampant or not too common because the choice is still limited, example is offering services to earn bitcoin like selling and buying goods or rendering any services and then the payment method is bitcoin you earn bitcoin without using Fiat to buy it, another method is through mining, this choices are limited but definitely not off it
Although there are still some way to own Bitcoin without using fiat to buy it directly, as you mentioned. However, at the end of the day, whether you mine Bitcoin, accept it as payment, or receive it from any other source...all of those are still tied to fiat and their value is measured in fiat.
You need fiat to own mining equipment, pay electricity bill, buy goods and build a business before you can offer services or receive payment in Bitcoin. As you can see, before you can own Bitcoin without using fiat to buy it directly, you still need fiat to get started.
Fiat is the primary unit of account in the economy, so being independent from it is impossible.