As you said, it depends on the channel's liquidity. If the amount you want to transfer with lightning exceeds the channel's capacity, then you can't transact it. The limit when you send via lightning is the channel's sending capacity. The limit when you receive via lightning is the channel's receiving capacity.

Suggestion:  For any question you have about LN, make it in the FAQ.

IF channels (other route hops before destination) had capacity then splitting can be done.
IF user has multiple channels and multiple balances to have that option
many if's you forgot to mention

he is not talking about the value HE has. so advice about HIM rebalancing is not the issue. its about making a payment along a route to a destination.. the liquidity of the route and the average value routes have across the network to have a good chance of success every time.

he is talking about the "payment success" rate thing.. like the near 100% for sub$1 amounts, the 10% success rate for pizza amounts in 2018.. or even this example more recently

maybe better to try to re-guage what a "payment success" % rate would be for 2021 for different amounts and actually answer the guys question rather then hide the issue with a "doesnt matter, just use LN whenever you want".. because from your own experience of 389 fails.. your experience is not a "doesnt matter just use LN whenever you want" thing, is it?.. heck you even had 5 channels and still had a 73% fail rate

even you know that routes need available balance along the route of multi-hops. and it does matter if one of those hops is bottlenecked. the guy wants to know whats the current easy amount that should pretty much always go through

your answer of "if you send many small amounts" is empty. as he was literally asking what "small amount" is, before you even said it..

EG most people are not going to open 5 funded channels just to buy the occasional coffee or pizza. most will just want to open one channel

so imagine in the non-utopian world(called the real world of real use). someone wants to buy a $18 pizza
but between the buyer and the pizza place there is a bottleneck
the bottlenecker only has $10 spare. and you want to send $18. sending it as 3x of $6 instead, is still going to fail.. because the bottleneck still only has $10!
meaning first 3rd, the bottleneckers $10 becomes $4, when sending $6
then the second 3rd fails because only $4 isnt enough to send $6
then the third 3rd fails because only $4 isnt enough to send $6

so the payer cant then send $18 to its destined destination to buy a $18 pizza because only a third can get through

so its not as easy as 'dont worry' as you pretend. and deep down you know it... you have personally experienced it. having over 380 fails with amounts under 0.0096btc (11% of your capacity)
so be honest, your now a big part of the altnet known as LN. so be part of the honest dialog about limitations and issues. how about try to actually gauge what "small" is in regards to "payment success"

if the largest 'success' you had was 11% of your capacity.
but you had a success:fail ratio of about 143:389.. atleast be honest about it and not pretend LN is easy and use whatever you want

I guess google might help you out. I found this article from binance it says

I don't know if its really the fixed amount to transfer in the lightning network but that's 20~ish cents USD as of writing and it's too small to be considered. I guess there's no need to worry about how small the transaction is but how large and frequent is.

That's an amount of minimum amount to transact on chain, not for off chain. Afaik, off chain LN transaction has no minimum but limitation on big size txs as mentioned above though personally I haven’t experienced LN a lot of times.

Usually, the Bitcoin(talk) community doesn't agree unanimously on anything

Personally, I base my choice between LN and on-chain on fees. At the moment I draw the line for making a LN-payment at less than 1mBTC (100,000 sat). Let me explain why: on-chain, 1 sat/vbyte is often enough, so I can make a transaction for less than 200 sat. With LN, I use either BlueWallet or Phoenix Wallet. The former is custodial and charges 0.3% to 1% in LN fees, the latter is only custodial when opening channels, and charges 1% with a minimum of 3000 sat to open a channel. That means, apart from other fees, a 100k sat transaction costs me up to several times more in LN than on-chain.
I can reduce my fees if I fund Phoenix Wallet using LN instead of on-chain, and at some point in the future I might switch to another LN wallet again, but for now this fits my needs.

Note that on-chain fees aren't always this low, so it doesn't hurt to keep some funds in LN. Funding a channel is much cheaper at 1 sat/byte than when fees are high. So I keep some funds on LN as an insurance against higher fees later on.

You can do some experiments when you pay. In many cases, using Lightning for large transactions is actually not cost-effective. Everything needs to be practiced. If you don't try it, how can you know the result.