I've heard this question asked before, and the answers are all over the map. I've read many of your query posts, but not all. If you've already addressed this, my apologies.
When querying, should you include mention of works published on websites--like for example if you been a long-time contributor at a certain site that highlights your work, and have a dedicated page there?
Do professionals in the agenting business really care about short stories, personal essays, articles published online? Do agents or their gatekeepers even click the links to check such work out, or are they just considered an encumbrance in the way of making a decision about the work the writer is seeking representation for?
You're confusing platform with writing credits.
A writing credit is work that has been curated, edited or selected in some way. Most work published on websites isn't curated. You submit a post, it's posted. That's GOOD for your platform, but it's not a writing credit.
The best example I can use is this blog: these posts are not writing credits. I hope the posts are well written, informative and useful, but there's no one looking over my shoulder saying "no, that post is awful, you can't use it." This blog IS platform: it's an indication of how many readers would know my name if I published a book.
If you have a regular page on blog, that's terrific, but you list it as platform. If you have short stories published online you mention it as a credit if there was an editor saying yes/no in a submission process.
Generally I do not click links in a query letter. I look at your query, and I look at your pages. I'm only concerned with the work you've sent me right then. IF I like the concept and the writing is good, and I've requested a full, then I swim over to get a more complete picture of your body of work.