I wouldn’t say for sure that it is the best long term hold, but it is definitely a more stable investment in relative. The outlook for Bitcoin wasn’t that appealing when its scalability issues become apparent during the time when Bitcoin was all over the headline. However, with the introduction of Lightning Network and given the current market dominance of Bitcoin, I think that it is definitely here to stay. The more people joining the cryptocurrency revolution, the more Bitcoin value will appreciate ( given it retains its current dominance ). I am not too sure if it will be the ” best ” long term hold, but I bet it will bring you some decent return in the near future.
I don't think it's one of the best long term holds given the very high quality alternatives that have much greater appreciation potential, but I think you're right in thinking that it will be around for a long time . . . being the bluest of the crypto "blue chips".