Meme coins price will gradually decline it's a nature of meme coins, these are pump and dump coin so meme coins will not stable for long time, every new coin make hype in the early stage then start dumping so notcoin and dogs are not different. But everyone will never buy meme coins, mostly sellers who participated in the airdrops, they don't complaining because they got free money, who's buy such meme coins from their own money they are complaining after price dropped.
It depends on the meme. There are brands that have been around and remain strong for more than 100 years. Memes like "coca cola" have obviously become more valuable over time, not less.
Some memes will obviously die, and some may not grow. But some will be huge. Memecoins are a risky investment, but there's clearly upside e.g. Dogecoin and so many of the others.
(And for most average consumer investors, "Bitcoin" is just another memecoin too
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