With the many changes, Google applies with recent broad core algorithm updates, it’s getting more difficult to rank using spammy tactics. It’s a no-brainer that people should wear white hats and ditch the black hats.
Yes, Google’s algorithm is stricter now. If you want to rank, you should follow Google’s guidelines and stick with it. However, it is arguable that there are still strategies outside of Google’s guidelines that people still consider doing.
This practice is called Gray Hat SEO.