The problem with this tool, like every other multi-SQL-flavor-SQL ORM and query builder, is that it requires users to learn yet another language. In addition to Node.js and SQL, users need to learn the Prisma query language. This is not trival, and users that are already accustomed to working with SQL will need to relearn PrismaSQL.
I think the best approach to this problem is a single-SQL-flavor query builder that attempts to match SQL as closely as possibly while adding in the niceties of being able to pass in JavaScript objects instead of raw SQL strings. Lets be honest: raw SQL-in-JS is no fun.
This would lead to PostgreSQL, MYSQL, SQLite, etc-specific query builders. Knex is close, but it ultimately doesn't work for most because it's missing some language-specific features (e.g. ON CONFLICT DO UPDATE). While this doesn't exactly meet the type safety benefits of Prisma, the benefits in ease of use and feature-parity of a language-specific query builder far outweigh the difficulties of learning a new query language like Prisma.