I've created a template override for the article view where the intro and the full text are invoked separately.
So, instead of
<div itemprop="articleBody">
<?php echo $this->item->text; ?>
</div>
I'm using
<div class="intro_text"><?php echo $this->item->introtext;?></div>
<div class="full_text"><?php echo $this->item->fulltext . JHTML::_('content.prepare'); ?></div>
The inclusion of JHTML::_('content.prepare') doesn't change anything.
Interestingly, content plugins load normally if explicit commands in curly brackets are not required. However, when {command} is required to load a plugin, said {command} is displayed as-is (raw and unprocessed).