&quot;altcoin&quot; is a highly misleading term for that. That term already means &quot;a cryptocurrency unrelated to bitcoin&quot;, typically having a different genesis block, subsequently an entirely different chain, and often further differences.<p>We already have a term exactly for what you&#x27;re talking about: a hard-fork (or just a fork if you like).<p>On either side of the fork is bitcoin, not the &quot;original&quot; bitcoin and an &quot;altcoin&quot;.<p>You&#x27;re also incorrect in other ways. In the case of most forks, you fork via voting by &quot;x% of the last 1000 blocks were mined by this implementation&quot;. Because of that, if everyone except the current miners use the alternate implementation, the new &quot;fork&quot; will never activate.<p>That&#x27;s because forks are <i>not</i> altcoins, but typically run on the same exact chain, behave compatibly with each other (prior to activation), and wait for consensus in mined blocks (to activate).<p>That method of voting does mean that only miners get a vote. It&#x27;s not because they validate all blocks, but rather because mining a block is the same as voting in basically all fork-consensus-algorithms so far.