First, SEO Value is updated very frequently, so from one week to the next it is hard to know what algorithm changes will take place.
Second, I’ve seen the SEO value stay after a domain has changed hands, but it’s not universal. Any major changes to structure and content will be detected, and can easily result in changes to the SEO value whether the domain stays in the same hands or not.
Third, domains should be purchased because the name means something, not because there is SEO value. Yes there are some prominent people who promote buying dropped domains for SEO value, but it is a risk in the long term.