ISTQB Certifications Under the Lens: Their Contributions to the Software-Testing Profession; and AI-assisted Synthesis of Practitioners' Endorsements and Criticisms. - Vehid Geruslu; Alper Bugra Keles; Sevde Degirmenci; Zafar Jafarov; Aytan Movsumova; Atif Namazov (CoRR, 2026)