I think this is a purely personal decision of each person. In this situation, it is not possible for very few to extract, since the cost of equipment and the production itself are more complex and voluminous processes. Due to competition, this type of mining was not possible for all people.
Indeed, the emergence of Bitcoin can be used for illegal purposes. But if the government starts working with Bitcoin, they can control everything. The only negative is the lack of central authority and control, as it is decentralized.
In my opinion it is very early to talk about such things. since the traditional banking system has been established for a long time and enjoys popularity among the population. In order to be a step forward in this area, the introduction of technologies and the use of innovations is necessary.
The cost of a BTC transaction is reduced because the network is evolving, increasing the speed of all processes. Despite this, the Bitcoin improvement plan aims to improve network bandwidth by scaling up in other transaction speeds. Reducing the cost of transactions will positively affect the development of Bitcoin.