Synth-pop = pop?
Is Synth-pop also pop music?
Most music companies like Billboard include all of Synth-pop music into pop chart. I have never see any chart site categorized synth-pop as new wave.
Similar question about a genre and subgenre relationship at https://allmedianetwork.helprace.com/i46-what-happened-to-caribbean-traditions-styles
We list Synth-Pop as a style under the larger umbrella subgenre of Punk/New Wave (alongside era-related styles like New Romantic and Sophisti-Pop).
Synth-Pop style: https://www.allmusic.com/style/synth-pop-ma0000002887
Punk/New Wave subgenre: https://www.allmusic.com/subgenre/punk-new-wave-ma0000011872
To be honest, no hierarchy of categorization of something as broad and interpretable as music is going to match everybody's taste and opinion.
If you take a look at our loose categorizations of subgenres and styles within the overall genre of Pop/Rock, we feel that Synth-Pop fits best alongside the styles listed above (as opposed to grouping it into another of the available subgenres).

"Synth Pop was one of the most distinctive subgenres of new wave. In the early '80s, a number of bands -- primarily British and heavily influenced by Roxy Music and David Bowie -- adapted the electronic innovations of bands like Kraftwerk for pop songs. Initially, in the hands of artists like Gary Numan, the Human League, and Depeche Mode, the sound was eerie, sterile, and vaguely menacing, since the electronics droned on relentlessly without any change in inflections. However, these first stabs at synth pop were transformed into danceable, synthesized pop by Duran Duran, who made the synthesized hooks warmer and catchier by grafting them onto a dance beat. Soon, a flood of bands followed Duran Duran's lead and although some of the groups weren't as infectious as that band, they nevertheless relied on the conventions of three-minute pop. Duran Duran became stars, while most other synth-pop groups were lucky to have more than one hit. There were some exceptions -- the Human League and Eurythmics had several hits, as did Howard Jones -- but the field was mainly occupied by one-hit wonders like A Flock of Seagulls. By 1984, synth pop had begun to die out, but the music had helped establish the synthesizer as a primary instrument in mainstream pop music during its time in the spotlight."