This is taken from Imam an-Nawawi’s book Rawdat at-Talibeen which was based on Imam Rafi’s writings, which was based on Ghazali’s writings, and Imam as-Suyuti conveyed it without criticism. That’s 4 major Imams of the Ummah that declared Kufr for neglecting the requirements of Da’wah. Not a good sign for today’s Muslims, particularly “imams” who literally abuse, harm, and drive Converts away.
Nawawi - Delaying Request for Shahada is kufr - Rawdat atTalibeen

The Medina Network is the only project in the US to comprehensively address the many problems Converts commonly face.

The Serious Needs of Muslim Converts : the Cause Behind the Medina Network Project