You. Are. Not. Producing. 8. MB. Blocks.
And you definitely aren't producing 32 MB blocks, which I understand is the new cap.
You're producing an average of ~50 or 60 KB blocks with a maximum threshold you've not come close to reaching.
so your worry about spam is empty
how can you argu about spam. then argue there is no spam because blocks are empty.
spam is all about incentive. without it, the spam won't happen but that doesn't mean it is not a concern for others as well. take 51% attack for example. there are shitcoins out there with such as low hashrate that you can attack then with a tiny altcoin mining rig and wipe out their blocks. but the price of these shticoins is so low that it doesn't give you the incentive to do it. you'll get less than 1 satoshi per coin for many of them!!! this doesn't mean these coins are protected against 51% attack it just means nobody cares enough to attack them.
same goes with spam, nobody gains anything by spamming a shitcoin with empty blocks. but many will benefit from spamming bitcoin even if the blocks were empty. from miners who earn a shitload of money to altcoins who pump their shitcoin because bitcoin fees go up. you seem to have forgotten that in 2017 when Dash was starting to pump with the motto "Dash will replace bitcoin" they were raising money on their forum to spam attack bitcoin with it. nobody ever says "Dash will replace bitcoin cash"!