I would agree with you if I was using it to commute. 😜
Even when just driving around on your own property, small solar panels provide little power. In Michigan where I live, considering available daytime sunlight, cloudiness, and sun angle, etc., solar cells produce only an average of 5% of their rated Watts on an annual basis. A 50 Watt panel would get you 50*24*.05 = 60 Watt-hours per day. A typical lead-acid battery loses about 5% of its 700 Watt-hour capacity per week just sitting without use. This is about 35 Watt-hours per day. A 50 Watt panel wouldn’t even keep two such batteries from self-discharging even if they were not used at all.