How to avoid massive 404 errors when deleting pages from a site?

Question

Search Engine Optimization

The site has a total of more than 400 pages, and 150 of them need to be deleted as absolutely unsuccessful. No one will rewrite, therefore, it is the removal that is needed, and a very radical one at that - without replacement with new, more successful posts. The question is, how in this case is it better to act in terms of SEO, because the deleted pages receive traffic from search engines, albeit a small one?
It is not a pity to lose this traffic, the point is that the massive 404 errors that begin to appear do not have a bad effect on the remaining pages. Of course, all broken links will be promptly cleaned up, the point is precisely in those 404x when people for some time will fall from the search results to already deleted articles.
I see several ways to do with the URLs of remote pages:

1. Massively redirect them to the main or html sitemap, for example
   
2. Bulk redirect to the "404 emulator page", where in fact there will be no 404 response code, but only a visual warning for the user that the post is no more
   

This seems to help avoid massive 404x and quietly hush up the situation. What do you think?

Answer 1

Do not redirect, do 404 and remove it from the sitemap. You can also remove it from the index in the webmaster (in google, for sure).
For a redirect to the main page, you will get pessimized faster, because the behavioral return to search results will indicate that the site does not have relevant content, while the page itself exists.
If it’s really scary, stretch the deletion for another month so as not to delete 250 pages at once, but for example, 10 per day.
Another normal option is to redirect from old pages to those that are tired, but this will only work if the remaining content is somehow relevant to requests to old pages.
Otherwise, you should not be afraid of 404. Even if it writes in the webmaster, such as "Error 404", this happens when the map is indexed, but not yet processed, and the page has already disappeared. Then you choose "Problem fixed" and Google webmaster then writes that everything is ok. Search engines are not as dumb as they were 15 years ago.