If product variants are used, then mails, messages and actions which are contributed to the product template are not shown in product variants. 

Depending from which section you are linking to the product area the user is headed to templates or products and mails, messages and actions are only added to template or product variants. 

Especially in the purchase area there is mostly a 1:1 relation between template and product, thus the contributes mails, messages, activities belong logically to both entities (template and product) 

Is there a solution or best practice in Odoo to show all notes taken on a product template also in product variants or is the best solution to hide the commenting area in templates or product variants? 

Thanks, Andreas