Not writing off their haki at all , I was never in the train that BB wouldn't have the basics of haki tbf
but I def dont think when it comes to it ,his command of haki is comparable to even current luffy . I think the main problem luffy would face with Blackbeard is the fact that one of his dfs completely negates his , and the other is easily the strongest paramecia in the story.
in the same token I expect the challenge for all the strawhats to be the df abilities that each BB commander was able to get in their hands. I would be very surprised if zoro were to go into the shiryu fight and already have his invisibility handled . Zoro is someone who coats his attacks in conquerors , who has solid armament , in a clash of just haki , I think there are very few people who would be better than him in that regard . very few fighters get to have it all when it comes to haki and df ( like luffy and kaido) , so personally I reckon his haki is good enough like kidd or law , but his df makes him a completely challenging fighter.
on burgess tho , not sure if sabo is that impressive or if burgess haki isnt that great either but he did get his armor smashed in dr .