Hi @bhuwan_b
Thank you for coming back to me. To be honest, I've had tried this approach in my project where the flicker impact noticeable if you have implemented pre-hide snippet through tag manager. Also other issues been seen like other third party script conflict with pre hide code (sometimes) execution wise and moreover it's impacting the core web vitals metrics like the default timeout values on anti-flicker snippets are set high (3 seconds) especially when we consider the limits that are placed on metrics like Largest Contentful Paint.
So we decided to go with hard coded with less time out and able to measure the impact of pre hide snippet code using User Timings
I've followed below article which explain nicely.
https://andydavies.me/blog/2020/11/16/the-case-against-anti-flicker-snippets/
Hope this helps.