For example, a major Google Analytics/Tag Manager consultancy called Lunametrics was acquired by Bounteous in 2018. The GA-related articles originally written on lunametrics.com are still ranking towards the top of search results, even though they are now under the Bounteous.com domain.
What I did notice on the Looka site was that there was no mention at all that the site has rebranded. Not even a "Logojoy is now Looka!" type banner on the top of the homepage with an explanatory blog post. A lot of SEO traffic comes through content marketing, where somebody clicks on an article link that's relevant to their query. I wonder if they removed or archived any of the blog posts or articles that were bringing in traffic.