http::payload xml tag value removal

If you specifically want to remove tags the most efficient means is likely an HTML profile:

Creating an HTML profile for tag removal

You create an HTML profile when you want the BIG-IP® system to act on certain types of HTML content.

1. On the Main tab, click Local Traffic > Profiles > Content > HTML .
2. Click the Create New Profile button.
3. In the Profile Name field, type a name, such as my_html_profile.
4. From the Parent Profile list, select /Common/html.
5. On the left pane, click HTML Rules.
6. On the Create New button, click the right arrow.
7. Select Remove Tag.
8. The Create New Remove Tag Rule box appears.
9. In the Rule Name field, type a name, such as my_remove_img_tag_rule.
10. Optionally, in the Description field, type a description of the rule, such as Removes the img tag with the src attribute.
11. On the left pane, click Match Settings.
12. In the Match Tag Name field, type the name of the tag that you want to remove from the HTML content.
13. An example of a tag to specify is the HTML img tag.
14. In the Match Attribute Name field, type the name of the attribute associated with the tag that you specified for removal.
15. An example of an attribute to specify is the src attribute for the img tag.
16. Click OK.
17. In the Available Rules list, locate the HTML rule that you want to enable, and select the adjacent check box.
18. Using the Move button, move the selected HTML rule to the Selected Rules list.
19. Click OK.

You could also use a stream profile within an iRule:

https://devcentral.f5.com/s/question/0D51T00006i7VPR/payload-manipulation-https-http