This differs per country. Some countries do block marketing messages, or some countries do block sender ID's. Other things that are restricted are SPAM messages, shady links, using brandnames like Apple. In some countries like India and Saudi Arabia, sexual content, gambling, alcohol etc.
For example the USA has very specific messaging restrictions. Financial offerings and SMS of this type of content are not allowed. This includes SMS related to loans, debt consolidation, investment, credit repair, tax relief, job matching and work from home programs. SHAFT: sex, hate, alcohol, firearms, tobacco content is strictly prohibited. Vaping or marijuana/cannabis or content relating to dispensaries falls under this prohibited content.