Also, this just Caught my attention..Block mined by BTC.TOP - only 1 transaction included..How?
You're welcome!
It's been happening less and less actually, but even several months ago I'd notice some pools in particular mine empty blocks. Unfortunately, (or not?), miners are free to decide which transactions in the mempool they want to include in the blocks they find. In fact, they don't even have to do it if they don't want to. The single transactions in those empty blocks are just the ones sending the block reward to their address (coinbase tx). Yeah, I guess at today's price, just depending on the block reward is now worth almost $200k.
Exactly why miners wouldn't want to include txs and earn fees, I don't really know. I'm pretty sure it doesn't actually slow down submitting their blocks, not since last upgrades.