Well, it is way less than the fiat or banking system. But still, bitcoin has it's problems.

For example, the current hashpower is 100 times higher than needed. 1% of that hashpower would be enough to hold the bitcoin network secure. So there is no reason for the "fee market" the 1MB block fans propagate. Miners need to trim down their miners. It happened all the time. Nobody mines bitcoin with GPU or CPU anymore now. Those miners were switched off. So when the reward is way way lower then bitcoin will still survive even with many miners switching off their miners.

And this hugely overloaded system has another problem. A study, some months ago, showed that ONE bitcoin transaction needs so much power like 1.75 average US-households use in electricity per day. ONE transaction. If the transactions has more than one input and 2 outputs then this power consumption grows even.

So at the moment bitcoin surely is not environmental friendly because the reward for miners is too high.