Well, trending and SEO are two different things.
The a SEO really works via long-term search engine optimization. SEO is something you work at over long periods of time, years and decades. When someone wants to learn something, they will likely go to a search engine Google or YouTube and type in the thing they are wanting to know. What pops up are the long-standing Web sites, articles and at this point videos that talk about those things.
If you want to know how cold if is on Pluto, go to Google and type temperature on Pluto. You are probably going to see a bunch of science and space Web sites like NASA, Wiki and others who have written article on Pluto and posted them to the Web 20 years ago. The same for YouTube.
The SEO is where a long-term strategy to place long-proven keywords and keyword phrases into your title, articles, blogs, videos description in order to better your long terms chances of ranking.
Trending is just flash pan of the moment, what ever is in the news today but gone tomorrow. Just waiting for something to trend, then jump on the band wagon isn't a very successful way to go about building a business nor a brand. You will always be at the mercy of whatever happens.
The only way to learn SEO is by doing it consistency over the course of about 10 years. Then you'll really understand SEO because thing that you wrote, blogged, vlogged about a decade ago is topping the ranks, still drawing views, readers and subscribers. Trends can't do that.