Lots of publishers have webpages aggregating the calls for papers at all that publisher's journals
https://www.sciencedirect.com/browse/calls-for-papers
https://us.sagepub.com/en-us/nam/open-call-for-papers
https://www.apa.org/pubs/journals/resources/calls-for-papers
https://authorservices.taylorandfrancis.com/call-for-papers/
Why can't they be aggregated beyond the individual publisher level?