Glad you love the datapack :) I'm afraid this feature won't be added, primarily because the goal is to only use reversible crafting recipes (e.g. 1 ingot -> 9 nuggets, and 9 nuggets -> 1 ingot). Bamboo to bamboo blocks is a one way recipe (although I'm not sure why!). However, I've outlined the steps to add this new compression below - you can do this for any other features you want too! Note that you'll need to expand my comment to see all of it.

Edit this file: ore-compressor/pack/data/ore_compressor/functions/check_compressible.mc_function
execute as @s run function ore_compressor:try_compress/bamboo

Create this file, and edit: ore-compressor/pack/data/ore_compressor/functions/try_compress/bamboo.mcfunction
execute store result score @s oc_item_count_1 run clear @s minecraft:bamboo 0
execute store result score @s oc_item_count_2 run clear @s minecraft:bamboo_block 0
execute if entity @s[​scores={oc_item_count_1=9..}] run function ore_compressor:check_space
execute if entity @s[​scores={oc_success=1}] run function ore_compressor:compress/bamboo

Create this file, and edit: ore-compressor/pack/data/ore_compressor/functions/compress/bamboo.mcfunction
execute run clear @s minecraft:bamboo 9
execute run give @s minecraft:bamboo_block 1
scoreboard players set @s oc_success 0
execute run function ore_compressor:try_compress/bamboo

It's certainly possible! I don't want to change the base version that I'm distributing, so I'll just let you know how to do it yourself.

Inside the datapack, go to the folder data/ore_compressor/functions/try_compress. There is a file for every item that can be compressed. For each of those files, change the following line:

execute if entity @s[scores={oc_item_count_1=9..}] run function ore_compressor:check_space

to

execute if entity @s[scores={oc_item_count_1=10..}] run function ore_compressor:check_space

Basically, change 9 to 10 :)