@tuhao
As @
percysmith said, this won't work for majority of companies because bigwigs who travel like earning the perks of FF elite status which they can use for personal travel. Also for the company I work for (and I suspect many others), they don't see FFP earning as a cost to the company so they don't care if employees earn miles/status on company travel. In fact, those that do earn status tend to see it as a benefit of company travel which makes them happier workers (free of cost to the company), at least in my personal experience. CX taking away lounge access from business travelers will only solve overcrowding by having business travelers actively avoid taking CX as much as possible at taking other airlines since I do not see others following this kind of practice if it is implemented.
Also, how will this work in reality... if a business traveler takes CX in J or F they don't have lounge access but if they are taking a OW partner J or F they will have access since OW rules state they do?