Can warming up emails for too long hurt deliverability?

I bought one of my domains in mid-March and one in mid-June and bought three emails on each but honestly, I have sent zero real emails to any prospect. What I have only done is kept them on warmup since the day I bought emails on those domains, which is six months warmup for three emails and three months warmup for three other emails.

And yesterday I wanted to see if emails are landing in inbox. So, I sent one email from each address I have on my domains to Gmail and Outlook, but they were going to spam.

I have also checked my domain health using platforms like MXtoolbox and a few others. But they were not showing any blacklists or DNS errors.

I am worried if sending automated emails for this long have hurt the deliverability.