With "deletion" you're simply advancing the moment, they're supposedly "deleting" your data; something I refuse to believe, they actually do. Instead, I suspect they "anonymize", or effectively "pseudonymize" the data (as cross-referencing is trivial, when showing equal patterns on a new account; would the need arise). Stagnation wouldn't require services to take such steps, and any personal data remains connected to you, personally.

For the Gmail account, I would recommend: not deleting the account, opening an account at a privacy-respecting service (using Disroot as an example), connect the Gmail account to an email-client (like Thunderbird), copy all its contents (including 'sent' or other specific folders) to a local folder (making sure to back these up periodically), delete all contents from the Gmail server, and simply wait for incoming messages, at the now empty Gmail account.

If a worthy email comes in: copy it over to the local folder, and delete it from the Gmail server. For used services, you could change the contact address to the Disroot account, and for others you could delete them, or simply mark them as spam (and periodically emptying the spam-folder). You may not want to wait for privacy-sensitive services, to finally make an appearance, and change these over to the Disroot address right away.

I've been doing this for years now, and my big-tech accounts remain empty most of the time. Do make sure to transfer every folder, and make regular backups!