Yes,
The issue is that each line is added line by line to frr (with ALOT of overhead since it will fire up python and all kind of stuff) instead of create a single file and batch it into frr once all lines of the config have been processed.
Similar occurs for firewall rules aswell (but here the target is nft instead of frr).
See this task regarding this issue: ⚓ T5388 Something is fishy with commit and boot times when more than a few hundred static routes are being used
And this for a similar forumthread: Very long time commit