Likely text containing URLs, though, which your email client likely helpfully auto-formats into links. Which is why spammers would bother. They need you to go visit something to make money.
There are types of bulk unsolicited email/web-comments which involve text without links, but they aren't spam per se; they're (the initial bait emails for) scams.
(And the usual solution to scam postings on forums, is to prevent people from sharing any off-forum contact details, except maybe via forum private message. No Nigerian prince is going to run their whole scam through the forum; they want/need to convert you ASAP into having a non-intermediated conversation with them. So they won't bother with any forum where they can't stuff their email address / Telegram handle / etc into each post.)
There are types of bulk unsolicited email/web-comments which involve text without links, but they aren't spam per se; they're (the initial bait emails for) scams.
(And the usual solution to scam postings on forums, is to prevent people from sharing any off-forum contact details, except maybe via forum private message. No Nigerian prince is going to run their whole scam through the forum; they want/need to convert you ASAP into having a non-intermediated conversation with them. So they won't bother with any forum where they can't stuff their email address / Telegram handle / etc into each post.)