It's possible to search for videos on Youtube excluding shorts using Google. To do this, we use the site: search operator with a URL prefix that only long-format videos should have. For example, if you search on Google for:
quick crafts site:youtube.com/watch
You'll get results from Youtube that are long-form videos, rather than Youtube shorts.
Explanation
The code above works because Youtube uses different canonical URL formats for long-form Youtube videos and short-form Youtube videos.
For a Youtube video with an ID dQw4w9WgXcQ, we can view it through two different URLs:
https://www.youtube.com/watch?v=dQw4w9WgXcQ
https://www.youtube.com/shorts/dQw4w9WgXcQ
The first URL is declared as canonical when the video is long-form, and the second URL is declared as canonical when the video is short-form.
Note that both URLs will work for any video.
If we try to use the /shorts/ URL with a long video, it redirects to the other URL. If we try to view a short video with the long URL, it shows the video in the normal interface instead of the TikTok-like interface Youtube shows for Shorts.
This means that a single Short can be viewed through either URL format. When things like this happen, search engines need the webpage to declare a canonical URL that they will use as the preferred one in the results. The canonical URL is what the link goes to when it appears in the search results.
For Shorts, the canonical URL starts with /shorts/. This means that none of the Shorts on have a /watch URL. When we use the site: operator ending in /watch, we filter all shorts from the results.
Conversely, if we used site:youtube.com/shorts/ this would search only shorts on Youtube.
Caveats
It's possible that some Shorts will be indexed with the long-form URL, so they won't be filtered by this method.