[Sn1F3rt]

Well, freenom logic is simple.
When you get high traffic, they take your site and sell it to advertisment site so they can get money from you if you are really interested in that domain.

Exactly as @ikk157 said, then it's a perfect scam instead of being a reputable free domain provider. If you're to spoil the whole idea of a person who might not be able to afford a domain, but has a great potential in his project, then I'd say it's better not to.

I only use Freenom domains for the hostnames of my VPS, since all of my other domains are behind Cloudflare and so no question of cancelling a domain with almost zero traffic.

On a personal note, I'd recommend using a subdomain from https://freedns.afraid.org or https://eu.org if you really can't buy a domain but need a webspace for production purposes. Even if you're to request nameservers access in FreeDNS or wait a fortnight for approval in eu.org, at least it's better than having an instant domain and getting scammed afterwards when you end up losing ownership of that domain which you cherished.

Regards,