DOGE could go all the way to $1, if Bitcoin goes on a long-lasting bullish trend. A target price of $100k per BTC should keep DOGE above the $1 threshold. It doesn't need Elon Musk to succeed. Don't get too excited about it, especially when it's a "meme coin". There are new projects out there with better features than Dogecoin.
Bitcoin has to go x4 for that price but with Dogecoin going to $1 needs more than 10x of gain. While it's known that it's almost there during its prime peak but as you've said that if Bitcoin remains to be priced at $100k on the next bull run, you're right that it should be sustained for a very long time because that will also push the price of it, not just Dogecoin but also other altcoins. But on these market of altcoins, it's tough to get back on peak when it's from there already.
Why would investors pour their money into a "meme coin", when they could put it all in a serious project with real use cases? Bitcoin, and Ethereum is where the money is. The crypto market is speculative by nature, so expect the unexpected. Who knows what the next big thing in crypto will be? Just my thoughts

They're all for the quick money that's being pushed by huge and retail investors there. It's like a seasonal type of trading if it's about these meme coins.