If bitcoin follows the current market history then there's a possibility that we will see it increase threefold like what it did last bullrun so there's a possibility that bitcoin will go more than just a 100k but I could be wrong though, I don't know where you got your notion that 2024 is going to be the last bullrun because afaik there's still a lot of bitcoin yet to be mined.
Actually I think it's a hope not that 2024 is really going to be a certainty about the bullrun to reach $100k but the hope is there because of course in this case the benchmark is probably to the halving and when that time happens of course there has to be some indication to make bitcoin lift and 2024 is a big hope before the halving comes.
But regardless of whether that happens or not we still have to wait and I think it's still worth it to look forward to. As for when it doesn't happen, I think it's not a problem either because sooner or later the bullrun will arrive and $100k is still very possible to happen.