Some good comparisons there OP. Compared to some of the other altcoins, Dogecoin actually hasn't done too bad in the past 2 year period.
Dogecoin November 1, 2018 High- $0.004 USD
Dogecoin November 1, 2020 High- $0.0029 USD
Source:
https://finance.yahoo.com/quote/DOGE-USD/history?period1=1447459200&period2=1605312000&interval=1mo&filter=history&frequency=1mo&includeAdjustedClose=truePersonally I feel that anything other than a very short term investment with altcoins is highly risky. Most altcoins are very influenced and affected by Pump & Dump schemes and unless you are able to watch the market for your altcoin holdings nearly 24/7 you are likely to miss out on the highs and lows. For instance you could be away from your phone/computer for 24 hours and have missed your altcoin catapulting to its All-time High and then dropping down to its All-time Low shortly after once all of the big traders/holders dump their coins.
And that could be the evidence that not all altcoins were shitcoin. Yeah, they haven't recovered as Bitcoin did right now but I believe that there is another season for them, it is just it isn't their time.
Now getting back, that is the reason why most of my holdings are in Bitcoin. The fact that Bitcoin is the most popular coin among all the cryptocurrencies that is why it getting much attention and being purchase by newcomer investors. The number of users is increasing and giving the reason for its demand to increase as well, in addition, those companies who are venturing to the use of Bitcoin makes a big impact as well.