I think that hedgerows are an excellent means of establishing perimeter fencing, and paddock delineation.
It is a slow (at nature's pace) way to
fence a property with minimal imports, and associated costs.
"Hedge laying", on the other hand is extremely labor intensive to get it established.
It is a throw back to an era when 'unskilled' farm labor was cheap and plentiful.
Trying to duplicate it today, it could be difficult and expensive.
Enough labor (at minimum wages) could easily cost you more than having professional fencers com in and install a first rate traditional
fence. A traditional fence will need some repairs every decade or so, but likewise, a laid hedge/hedgerow also requires periodic maintenance. (No posts and wires, but plenty of labor.)
Laid hedges and hedgerows both have the added benefit of improving soil quality, and helping to provide a balance of beneficial fauna to the landscape. Posts and wires offer no benefit, other than delineating areas.