Module development and code questions

Hello Drupal developers. I have a question about the retention time of temporary files in Drupal's filesystem.
If you don't mind, could you please answer the following two questions?

1. Why is it set to take 6 hours to delete temporary files in the first place?
Why is the shortest time set for deleting temporary files in Drupal's file system to 6 hours? I doubted that a shorter time was not available.

this error keeps showing in the browser so I can't even clear the cache in Drupal.

We are planning to implement search feature using the Mongodb as search index server. Is there module that helps to add the Mongodb connector as Search Server and then add search index mapping to push Drupal content to Mongodb Server.

Any equivalent module in Drupal 9 for https://www.drupal.org/project/mongodb_indexer

Also please suggest any contribute module to use the search query from Mongodb Index to display result in Drupal CMS.

I am migrating a Drupal 7 site to 10, and currently I have the PHP code at https://www.drupal.org/node/1893978 working with Rules, but there is no way to do this with Drupal 10 and Rules as there is no form actions with Alpha.

ECA looks promising, but I could not figure out a way and it may be too bloated to use ECA (will need 4 or 5 mods enabled), to achieve this.  The below code is what's being used currently, how can this be modified into a simple module to work in Drupal 10?

I have enabled tfa for one of the users. The message "TFA Enabled successfully" is displayed. But when I login with the same user credentials and the login was successful without asking for verification. I tried giving the hardcoded hash value as well. It shows that access is denied (It is not the right way). It is not redirecting to the verification page. What changes should I make for the verification page to be displayed.  My drupal version in 9 and tfa version is 1.0. I have installed the modules through composer.

I have an big issue.

I use a csv file as entry in order to generate/create dynamically node in Drupal 10 (inside a hook_cron).

But even for 10 lines of data I have a mysterious behavior, the code wants to create the same content node with the same entity_id value.

Event if I create data line by line (csv) and when each data is different.

The error is about integrity constraint violations duplicate entry.