Here on Steem there are essentially no bitcoin maximalists and everything is filled by altcoin fanatics. Being on an altcoin powered platform this certainly is no surprise.

I personally am a much bigger supporter of BTC than for example steem but would not call myself a maximalist. I think that a healthy competition will only advance crypto further. That being said, I think it is due to issue a word of warning. Most of the altcoins are nothing but scams, unless or redundant, even in the top 20.

Outright scams

We have seen how these work. They essentially promise free money and are build as a ponzi scheme. These collapse as soon as the bull market ends because the only thing supporting them is hype. The best example is bitconnect, but new scams are waiting to steal your money in the next bull run.

Fake tokens

There are lots of alright projects that have added a token just for the purpose of drawing money in an ICO and collecting user fees. But these tokens could be removed and implementations without an extra token are possible. It is just a matter of time until somebody implements the same functionality clean and thereby making the service cheaper to the users that no longer need to pay some random token holder to participate.

These tokens may survive for some time because there is limited incentive to implement the code without directly monetising it, but it will eventually happen. So my advice is asking yourself why a certain token is necessary, or if the project could be improved by entirely removing the token, or replacing the token with ethereum (or whatever is the native smart contract token) or bitcoin.

For example I think that REP is a necessary token required for the game theoretical security of the prediction markets on augur. But MAKER seems to be an 'add on' token just for 'governance' and collecting fees. Or look at BAT. Why do I need to donate an invented token to content creators when I could just pay them BTC.

Steem is another necessary token as we need inflation to make the platform essentially free to use and pay content creators. I still think that the financial model is very speculative and better solutions may appear any monet.

Overhyped Technology

A lot of the altcoins are massively overstating their technology or use case. They could work, but it is very unclear if there is a market at all or if they can deliver their promises in a real world environment. Most of these are in fact impossible and need a lot of technological advancement. We will not see them successful within the next 10 years and then there will be newer cleaner implementations.

Redundant coins

A lot of the coins are just clones of other projects that just change some minor details. How are these adding any real value to crypto? Most of these will eventually be forgotten and disappear. See for example Bitcoin gold.

Utility Tokens

Utility tokens are a solid idea and I think they have a good future on the blockchain. For example your local supermarket can give you promotion tokens on the chain; or car sharing pools may have their own utility token for renting cars. This opens up trading on a secondary market and that may be beneficial for the project. But these tokens should have an almost constant price and be a very non-speculative investment. They are fundamentally different from fundamental crypto coins such as bitcoin. There is no reason to believe they would increase in value even when the underlying project becomes successful.

Smart Contract Platforms

Bitcoin has already achieved real world adoption and despite the bear market is showing very healthy vital signs. The same is not true for smart contract platforms. All of those still have a fundamental scaling/security tradeoff problem. There are many approaches but basic functionality is just not there yet. While I believe in the revolutionary potential of smart contracts I think that the chain and technology that will enable mass adoption does not exist yet. Investing in these coins is very speculative.

Summary

In the top 20 I think there are only very few projects that have a realistic chance of breakthrough adoption. Everything but BTC is very speculative. It might pay off massively, but there is a solid chance to have total loss.