Buddhism has never been an evangelical religion, nor should it become one. However, clear explanation of the Buddha's teachings should be made available to people who are interested. The Buddha showed the path to happiness, and it is desirable for this to be made accessible to others, so that they can benefit from it. This is the duty and responsibility of Buddhists who have compassion for others. First, if oral teachings were given in the language with which people are most familiar, the language in which they are educated, then they could understand the meaning better.
Colloquial language communicates much better to lay people than does classical language.
For scholars and serious practitioners, knowledge of Pali, Sanskrit, and ancient Chinese is necessary, but for the general public and young people who are used to television colloquial language and everyday examples are more suitable. I wonder how many others there are who avoid going to teachings or reading books because they cannot understand the language well. Secondly, it is essential that Buddhist principles be clearly and logically explained. Today's youth is well-educated. They have knowledge of science, philosophy, psychology, and so forth.