Google has drastically reduced the indexing of our website

We are facing a problem and may need some help. We made a few changes a month ago to speed up the site and make general SEO fixes. Immediately after doing so, Google said our website took 2-3x to download a page and slowed down the crawling of our website. Previously, we were at 30,000 pages per day and now at 4,000. It is also decreasing.

The "time to download a page" has increased from 150 MS to 300 MS. I thought it was about the speed of the website (which was a head-scratcher since we're faster than before), but it turns out that its http connections, according to Neil Patel google-search-console-crawl-stats are /. The only thought that could have raised the HTTP connections was possibly the addition of a schema, since there is not a bunch of on the page, but in truth that does not make sense to me.

Has anyone ever done something about it? What could be the cause?