Hello simo ! Yes I can view the Web Map properly in the viewer! And the map sharing's properties are as desired, which is group only. So is the View Layer featured in the Web Map.
Earlier yesterday, I could not get the Web Map to appear in Collector. By adding this snippet in the Web Map properties, I was able to get it to show. That being said, the points hosted in the view do not appear on the map (although, in the layer menu, I can see the layer in Collector).
Here's the snippet I added :
empty_webmap = WebMap()
empty_webmap.add_layer(view_item, options={'title': view_name})
webmap_item_properties = {'title': str(municipality) + '_Implantation',
'snippet': str(municipality) + '_Implantation', 'tags': '2019',
"typeKeywords": ['ArcGIS Online', 'Collector', 'Data Editing',
'Explorer Web Map', 'Map', 'Offline', 'Online Map', 'Web Map']}
empty_webmap.save(webmap_item_properties)