Bloated yoast_post_meta table

I am using YOAST SEO plugin and my YOAST_POST_META table is getting very large.
I have about 5000 custom posts (discount coupons) in a dynamic website.

The current yoast_seo_meta table is 790 000 rows and 33MB.
This is 40% of the entire wordpress database.

I could think of one cause of this problem. Every hour I am replacing the discount coupons using WP All Import. Last week I increased speed of the import process by disabling the “do_action” function during the post import.

Quote from the WP All Import website:

Disable the do_action to Speed Up Imports
Every time WP All Import creates a new post it uses wp_insert_post. The problem with this function is that it wasn’t designed for creating a lot of posts at once – it was designed for creating one post at a time. It can be slow, and part of the reason for the slowness is the do_action calls.
? Solution
In Manage Imports ? Import Settings ? Advanced Options you can enable the Increase speed by disabling do_action calls in wp_insert_post during import feature.
This will prevent other software in your WordPress site from interacting with posts as they are imported, so other plugins that are supposed to automatically do things to new posts may not work for imported posts.

? How do I clean up my database? WP Optimize is not taking any rows of the yoast_seo_meta table.
? How do I prevent this table from bloating?
? Should I re-enable do_action in WP All Import to prevent this problem?

I am looking forward to your response!