while I went in on a single portfolio of Bitcoin and when the unexpected of FTX hack happen the whole market in shamble and his altcoin portfolio have dropped above %800+ but my bitcoin holding still maintains some level of stability.
To be fair if you look at the long term history of bitcoin and altcoins (meaning over the past 10 years for example) you can see that altcoins are always dumping without needing something like FTX hack happening. Such hacks only speed up that dump in short term. But when it comes to bitcoin the same thing only causes a drop in short term due to panic sells which will be recovered, something that won't happen for most altcoins (although some would recover before dumping again).
P.S. You can't lose more than 100%. Only gain can be higher than 100%.