The beautiful thing about Google workspace inboxes is that if you play it right - they will NOT get banned. We never had any account banned for over 5 years.
The risk is the ‘spam score’ and being marked as spam, there warm up tools that help with spam score and making sure your data is valid and not bouncing (invalid emails) to keep your health score high.
If you do it right, depending on the offer and who you send the emails to, you should land 40-90% of the times in the main inbox - not spam.
The infrastructures that will get you banned eventually are cheap SMTP that most spammers use.
With Google workspace inboxes you want to scale horizontally which means - in order to send a lot of volume, you need to create many inboxes and send up to 25 cold emails per day per inbox (once it’s fully warmed up)
Let me know if you have any more questions