Comment by js2
Main disadvantage is cost. Looking on Amazon, it's $1.61/ea AA lithium vs $0.62/ea akalaline. That's Energizer vs Energizer. Amazon Basics AA alkaline are $0.32/ea. (Unlike alkaline, knock-off lithium aren't much cheaper than Energizer.)
If I had a dollar for every device that I've seen ruined by leaking alkaline cells, I could buy a palletload of lithium cells.