I'm not a crypto analyst, but I've been watching the market for a few years now, and to my eyes there does seem to be the kind of pattern you described.  I've always assumed that since there is a finite amount of money being invested in the entire crypto market, sometimes it gets a bit lopsided--like right now it looks like most of the money is going toward bitcoin, which is boosting its price.

And yeah, I think altcoins will catch fire again, and for some reason I think it'll probably be soon.  I also hate to admit this since I'm a huge supporter of bitcoin, but lately I've been trading my bitcoin for some altcoins that I can stake for interest/dividends.  The prices seem very low, and bitcoin's price is sky high, so I figure it might be a good buying opportunity right now.