You'll change behavior of Bitcoin script which depends on block height as it's spending condition. LN's HLTC depends on block height., which give additional reason to reject this idea.
Sure this is possible but these type of proposals were presented about maybe 10 years back. You need to remember if you do this then the block chain size will increase and so will the required bandwidth. So what will happen is that it will take more resources to secure the network by node operators. Eventually the resources will be too much so node operators would stop providing the service.
The solution to this problem is to leave the main bitcoin network as is and just use l2 when you need to do frequent transactions. This way you can store your main balance on the main chain and from time to time keep some on some l2 which you spend daily.
Roughly it's just 2x increase. I expect Bitcoin node's hardware generally can handle that, unless it uses old Raspberry Pi, very old PC or very cheap VPS.