Oh yes it is!
Consider this HTML:
<a href="{{str}}"> and consider an input like:
" onmouseover="alert('GOTCHA')" You get the picture.
If your javascript is being injected within a tag then you don't need the angle brackets. I borrowed this off this similar S/O post: https://stackoverflow.com/questions/5696244/xss-is-escaping-and-sufficient
If you are interested in filter evasion like this consult:
https://www.owasp.org/index.php/XSS_Filter_Evasion_Cheat_Sheethttps://owasp.org/www-community/xss-filter-evasion-cheatsheet
This has all the common stuff.
As far as safety is concerned: Encode all the things! You never know how clever the attacker is.