So instead of having to do myproject@gmail.com
Be able to do hello@myproject.com
Google workspace is at least $6/mo which feels like too much if I have a few side projects.
If you don't want additional mailbox. Try Cloudflare email routing. Basically you'll route all emails incoming at hello@example.com to your gmail id. Then you can continue the conversation with just clicking reply all. Though not good in perspective of branding but best option for getting started.
One popular free solution for having a custom email domain for side projects is to use "Zoho Mail." Zoho Mail offers free email hosting for up to five users with a custom domain
Tandem