Does CTR Manipulation work anymore? Is it dead at this point?

Been using an SEO agency who's been focused on doing CTR manipulation for two of my businesses. Both GBP clearly show an increase in "directions" which is obviously where they target the CTR but it hasn't really done much for calls in. Granted, one of the GBPs is for an extremely niche, long sales cycle, contract based competitive business whereas the second GBP is brand new ~15 reviews and ~45 days for junk removal.

Been seeing some debate about the cost/benefit to CTR manipulation, considering bringing it in-house and terminating them if its still worth it.

from everything i've read, it can help boost rankings, but the downside is once you train google that your CTR is what they are seeing now, you kind of become trapped having to always have a CTR campaign going to keep those numbers up. so, you really need to also be working on other outlets to help your rankings.

CTR manipulation worth it. It depends on how you make the strategy or software to do it.

If you can do it above the radar and safe then you can get better results since ctr is one of the key ranking factors for gbp ranking.