Both the Apache and Jetty Http client libraries are capable of defaulting to the Java truststores when no system properties are provided. However, when cleaning up logging in
SOLR-15936 the Http2SolrClient no longer used an SSLContextFactory when the system properties were not used. This is a regression for users that use the built-in truststore.
Ideally we would be able to use both the default truststore and not give extra (useless) logging. If choosing one or the other, I think we should choose using the default truststore though.