From the documentation, I assumed that proof of burn is over and was replaced by proof of transfer.
So, how comes that the miner (configured according to https://docs.stacks.co/nodes-and-miners/miner-mainnet) sends the balance to 1111111111111111111114oLvT2?
Also, how long is it expected to take until the mined STX shows up in the wallet?
Mined STX shows up after a “maturity” window (100 blocks). And even in PoX some bitcoin will inevitably get sent to the burn address (e.g. during the prepare phase, or if all PoX slots are not full).
Ok, thanks for clarifying.
But is it really economic if still that much BTC get burned? When I checked 10 consecutive spends from the seed address, I got:
36% of the BTC amount being sent to the burn address
64% of the BTC amount being sent to BTC miners as fee
0% real PoX (spendable addresses not being the seed address itself receiving the change)
I wonder how appropriate stacking rewards can be paid when so much BTC just gets burned.
Also, the 100 maturity blocks seem to take pretty long. Almost a week ago, I got several log lines like this:
INFO [**********.******] [testnet/stacks-node/src/neon_node.rs:965] [relayer] Won sortition! Mining reward will be received in 100 blocks (block #*****)
Still, no reward shows up:
{"balance":"0","locked":"0","unlock_height":0,"nonce":0}
On the Xenon testnet, it took just a day to see that mining works.
Any update on this? Will the reward be sent at all?
I think the amount of of btc burned is very small amount Cycle #44 — stacking.club you can see more stats. From my understand some btc burned during the cycle is necessary of the the technical details. Maybe @muneeb can speak to that better… I remember asking that question once on Stacker Chats 
I wonder if @MattySTX has any info/research regarding the btc amount burn during PoX?