My mail opens for one second and crashes. Thought this might work. It didn't

I was moving junk / spam mails last week and I locked up my Apple Mail app,, the Mail app immediately quit, and repeatedly crashed everytime I tried to reopen it. I was in a panic because I had “fixed" the mail app before because I at least had a few seconds to work on the app before it would crash the last time this sort of thing happened, but this time, the crashing happened so fast each time I tried to reopen it that there was nothing I could do. After spending several hours working with Apple Support on chat and later on the phone trying different things, I still had no access to my Mail, and full disclosure here: I have “thousands and thousands” of emails on my iMac hard drive from many years of spending a lot of time working with emails.. Out of desperation, I got back on the Apple App store not knowing what I was looking for and ran across this app.. It was listed for $3.99 and I thought, I have to try something.. I purchased this app and had it run on my computer and it got my Apple Mail open on the first try. Sure, I had to sort through many old emails that were placed in “Recovered” mailboxes, but that was a small price to pay for getting my life, I mean my email program back. The best $3.99 I ever spent. Thank you Mail Optimizer creators...