That's sort of my reasoning as to why top 50 Alt-coins won't go down another 10% because Bitcoin has stabilized around high $60k, and with the upcoming halving, I don't think it'll plummet enough to drag the Alt-coins down further.
That said, Alt-coins don't immediately react to Bitcoin halving, at least not based on the previous cycles. That gives me a pause to see if I should wait to buy back in a bit later, or shrug this off and just buy now for the next uptrend.
It sounds like you are weighing Bitcoin stability and its likely impact on altcoins market. You are right that altcoin don't immediately react to halving as they have their own factors those drive their price movements, such as technological development, adoption and market sentiment. It was good opportunity to take entry in alts when last weeks Bitcoin price was hoovering around $69K. This morning Bitcoin has demonstrated impressive price movement and surged more than $3000, currently trading around $72,300. Thus, this surge in Bitcoin price might boost optimism among altcoins investors.