Why so empty?
I only realised this the other day, but when I was making a dogecoin transaction, it took ages to confirm. I was using dogecoin in this case because the fees are low and it's best meme coin.
Why did it take ages? The funny guy over at DMr3fEiVrPWFpoCWS958zNtqgnFb7QWn9D (who controls 6% of network hashrate) is deciding not to include transactions with a less than 1 dogecoin fee. This is fine, but it means that a lot of transactions don't go through for a while (0.206 Doge was my wallet's estimated fee at that point). Many wallets don't add the traditional "1+ full doge fee" to their transactions as it's not really necessary and while it's only small, it's still a bit of a waste to pay more for a txn than the required rate.
This miner is mining a bunch of empty blocks, meaning that they're not collecting transaction fees most of the time (unless there are >1 dogecoin fees on your transaction). This made me have to wait 3 blocks in order to send dogecoin. According to a quick search, adding transactions to a block is not resource intensive and therefore it makes no sense for them not to include them, and they won't solve the block any quicker.
Here you can see one of their longer "transaction-free" block streaks.